Document:

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                                                                     EXHIBIT 4.3

                                                                  EXECUTION COPY

                                 ENGLISH VERSION

                   AMENDED AND RESTATED MASTER LEASE AGREEMENT

         This Amended and Restated Master Lease Agreement (this "MASTER LEASE"
or "AGREEMENT") is entered into this 16th day of May, 2002, between MATC
Celular, S. de R.L. de C.V. ("MATC CELULAR"), and GRUPO IUSACELL CELULAR, S.A.
DE C.V. (f/k/a Grupo Iusacell, S.A. de C.V. (f/k/a Nuevo Grupo Iusacell, S.A. de
C.V.)) ("GRUPO IUSACELL"), and IUSACELL ARRENDADORA, S.A. DE C.V. ("LESSEE").

         Capitalized terms not otherwise defined herein shall have the
respective meanings set forth in Exhibit A attached to this Agreement and
incorporated herein by this reference.

                                    RECITALS

         I.       RECITALS OF GRUPO IUSACELL AND LESSEE.

         Grupo Iusacell recites that:

         a)       It is a corporation duly incorporated and validly existing
under the laws of Mexico, with the power and authority to enter into this Master
Lease and to comply with its covenants and obligations as set forth hereunder,
as evidenced by Public Deed No. 33,275 granted on August 6, 1998, before Public
Notary No. 195 of the Federal District, Lic. Ana Patricia Bandala Tolentino,
which first copy is duly registered at the Public Registry of Commerce of the
Federal District, Mexico, under Commercial No. 242,349, on November 3, 1998.

         b)       Its representatives are duly authorized and have the required
legal capacity to enter into this Master Lease on its behalf, and that their
authority has not been modified, restricted, revoked or otherwise amended since
the date on which it was granted, as evidenced by Public Deed No. 3,849 granted
on June 26, 2001, before Public Notary No. 212 of the Federal District, Lic.
Francisco Hugues Velez, which first copy is duly registered at the Public
Registry of Commerce of the Federal District, Mexico, under Commercial No.
168528, on July 4, 2001.

         c)       The terms and conditions of this Master Lease do not
contravene any of its obligations under any agreements, permits, concessions
and/or authorizations to which it is a party and therefore does not constitute a
breach of any of such agreements, permits, concessions and/or authorizations.

         d)       Grupo Iusacell has agreed to remain jointly and severally
liable for the obligations of Lessee under this Master Lease.

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         Arrendadora recites that:

         a)       It is a corporation duly incorporated and validly existing
under the laws of Mexico, with the power and authority to enter into this Master
Lease and to comply with its covenants and obligations as set forth hereunder,
as evidenced by Public Deed No. 1,557 granted on July 27, 2000, before Public
Notary No. 212 of the Federal District, Lic. Francisco I. Hugues Velez, which
first copy is duly registered at the Public Registry of Commerce of the Federal
District, Mexico, under Commercial No. 266651, on August 30, 2000.

         b)       Its representatives are duly authorized and have the required
legal capacity to enter into this Master Lease on its behalf, and that their
authority has not been modified, restricted, revoked or otherwise amended since
the date on which it was granted, as evidenced by Public Deed No. 1,557 granted
on July 27, 2000, before Public Notary No. 212 of the Federal District, Lic.
Francisco I. Hugues Velez, which first copy is duly registered at the Public
Registry of Commerce of the Federal District, Mexico, under Commercial No.
266651, on August 30, 2000.

         c)       The terms and conditions of this Master Lease do not
contravene any of its obligations under any agreements, permits, concessions
and/or authorizations to which it is a party and therefore does not constitute a
breach of any of such agreements, permits, concessions and/or authorizations.

         II.      RECITALS OF MATC CELULAR. MATC Celular recites that:

         a)       It is a corporation duly incorporated and validly existing
under the laws of Mexico, with the power and authority to enter into this Master
Lease and to comply with its covenants and obligations as set forth hereunder,
as evidenced by Public Deed No. 43,972 granted on October 5, 1999, before Public
Notary No. 1 of the Federal District, Roberto Nunez y Bandera, which first copy
is duly registered at the Public Registry of Commerce of Mexico City, Mexico,
under commercial number 253584, on October 27, 1999.

         b)       Its representatives are duly authorized and have the full
legal capacity to execute this Master Lease on its behalf, and that their
authority has not been modified, restricted, revoked or otherwise amended since
the date on which it was granted, as evidenced by Public Deed No. 43,972 granted
on October 5, 1999, before Public Notary No. 1 of the Federal District, Roberto
Nunez y Bandera, which first copy is duly registered at the Public Registry of
Commerce of Mexico City, Mexico, under commercial number 253584, on October 27,
1999.

         c)       The terms and conditions of this Master Lease do not
contravene any of its obligations under any agreements, permits, concessions
and/or authorizations to which it is a party and therefore does not constitute a
breach of any of such agreements, permits, concessions and/or authorizations.

         III.     RECITALS OF THE PARTIES. The parties recite that:

         a)       MATC Celular, Iusacell Celular and Lessee have previously
entered into a Master Lease Agreement, dated as of February 23, 2001 (the
"ORIGINAL MASTER LEASE AGREEMENT"), relating to the lease of space by Lessee at
certain Sites described herein.

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         b)       MATC Celular and Iusacell Celular have entered into that
certain Management Agreement dated December 29, 1999 (the "MANAGEMENT
AGREEMENT"), pursuant to which MATC Celular is acting as Iusacell Celular's
agent with respect to the licensing, leasing and subleasing of available space
on towers now or later owned by Iusacell Celular or certain of its Affiliates,
and pursuant to which Iusacell Celular and MATC Celular each have certain rights
to cause MATC Celular to purchase or Iusacell Celular or such Affiliates to
sell, as applicable, certain communications tower sites owned by Iusacell
Celular or its Affiliates, including the Sites described herein.

         c)       MATC Celular and certain affiliates of Lessee have entered
into that certain Purchase and Sale Agreement dated as of February 23, 2002 (the
"PURCHASE AGREEMENT"), pursuant to which such affiliates agreed to sell, convey,
assign, transfer and deliver to MATC Celular, and MATC Celular agreed to
purchase and acquire from Lessee, all of the right, title and interest of Lessee
in and to the Sites described therein, and the execution and delivery of this
Master Lease is a condition to MATC Celular's obligation under the Purchase
Agreement to purchase the Sites.

         d)       Lessee wishes to lease from MATC Celular space for operating
the communications equipment of its affiliates specifically described in the
applicable Site Lease ("LESSEE'S IMPROVEMENTS AND EQUIPMENT") and non-exclusive
use of certain rights of way granted under Section 1(f) of this Agreement
(collectively, the "PREMISES"), all on Sites to be transferred or sold to MATC
Celular pursuant to the Purchase Agreement at locations more particularly
described in a supplement to be executed in the form attached to this Master
Lease as Exhibit B, which form may be mutually amended by the parties hereto
from time to time (the "SITE LEASE"), each of which Site Leases shall be
governed by the terms of this Master Lease and which shall become a part of this
Master Lease as if fully set forth herein.

         e)       The parties desire to amend and restate the Original Master
Lease Agreement as provided herein.

         NOW THEREFORE, based on the above, the parties agree as follows:

         1.       LEASE OF PREMISES.

         (a)      MATC Celular does lease or own, and operates the Sites. Lessee
shall lease from MATC Celular the Premises within each of the Sites in
consideration for which Lessee shall pay rent as specified in Section 5 of this
Agreement and the applicable Site Lease, under the terms and conditions of this
Master Lease. Upon execution and delivery of a Site Lease with respect to a
particular Premises, each Premises shall become subject to this Master Lease and
the corresponding Site Lease.

         (b)      Upon execution and delivery of this Master Lease, MATC Celular
and Lessee shall execute a Site Lease with respect to each Site acquired on the
initial Closing Date. At each subsequent Closing under the Purchase Agreement,
MATC Celular and Lessee shall execute a Site Lease with respect to those Sites
being conveyed at that particular Closing. The Sites

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acquired on the initial Closing Date are set forth in Schedule 1 attached
hereto. The parties acknowledge and agree that at each subsequent Closing, the
list of Sites in Schedule 1 shall be amended to include the Sites transferred in
connection with such subsequent Closing, and such amended list shall supercede
any previous list of Sites in Schedule 1.

         (c)      [INTENTIONALLY OMITTED]

         (d)      The parties agree that either party may request the
registration of any Site Lease at the Public Registry of Property corresponding
to the jurisdiction where any Site is located, as specified in the corresponding
Site Lease, and all costs and expenses associated with such registration shall
be borne solely by the requesting party.

         (e)      As of the Commencement Date, MATC Celular will grant the
Lessee the use of the Premises as provided in the applicable Site Lease, which
Premises shall be ready to be used by Lessee, under terms of Article 2412 of the
Federal Civil Code and the corresponding provisions of the Civil Codes of the
States of Mexico, and shall comply with all of its obligations thereunder or
under the applicable provisions of the Civil Codes of the jurisdiction in which
any Premises are located.

         (f)      MATC Celular shall lease to Lessee and Lessee shall lease from
MATC Celular the Premises identified in each Site Lease, as of the Commencement
Date and under terms of this Master Lease. MATC Celular grants Lessee the right
to install and maintain Lessee's Improvements and Equipment on the Premises and
rights to install and maintain utility wires, cables, conduits and pipes on the
Site including over, under or along a right of way extending from a public right
of way to the Site, and to utilize a right of way for access to the Site as
described in Section 7(f) hereof and in the applicable Site Lease.

         (g)      If the Premises are a part of property leased by MATC Celular
under any agreement with the owner of the property (the "PRIME LEASE"), all
terms, covenants and conditions contained in this Master Lease (other than
Section 13(c)(i) hereof) shall be specifically subject and subordinate to the
terms and conditions of any applicable Prime Lease. In the event that any of the
provisions of the Prime Lease supercede or contradict the terms of this Master
Lease (other than Sections 3, 5, 6, 9, and 13 hereof), such terms of this Master
Lease shall be deemed deleted and superceded to the extent of the contradiction
as applicable to the space used by Lessee. MATC Celular covenants and agrees
that it will not agree, without the prior consent of Lessee (which consent shall
not be unreasonably withheld), to any modification of the terms of a Prime Lease
prior to the termination or expiration of such Prime Lease if such modification
would contradict any material term of this Master Lease and reasonably could be
expected to have a material adverse effect on Lessee. In the event the Prime
Lease expires or is terminated prior to the expiration of the Initial Term or
any Renewal Term (as such terms are defined in subsection (b) of Section 4), the
corresponding Site Lease shall terminate as between MATC Celular and Lessee on
the effective date of termination of the Prime Lease, and MATC Celular shall
have no liability to Lessee therefor. MATC Celular shall give Lessee written
notice of any such termination promptly following its receipt of notice from the
lessor under the Prime Lease. A copy of the applicable Prime Lease will be
provided to Lessee upon request, redacted as deemed reasonably appropriate by
MATC Celular.

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         (h)      The parties hereto agree that the terms and conditions herein
shall be and are binding upon and exclusive to each party hereto with respect to
any lease of space by Lessee entered into during the Term of this Agreement with
respect to any Site. The parties acknowledge that each Site Lease shall be
signed by MATC Celular and Lessee. Lessee warrants and represents that it has
the authority to execute and deliver this Agreement.

         2.       USE OF THE PREMISES.

         Subject to Section 3, the Premises may be used by Lessee only to
install, maintain, repair, replace, remove and operate Lessee's Improvements and
Equipment on or in the Premises for the purposes of a telecommunications
facility and uses incidental thereto in connection with the provision of
wireless telecommunications services including, without limitation, cellular,
PCS, wireless local loop, paging, and fiber optic and microwave transmission
services.

         3.       CONSTRUCTION AND ALTERATIONS.

         (a)      Lessee shall be solely responsible for all costs and expenses
associated with the purchase, installation, repair, maintenance and alteration
of Lessee's Improvements and Equipment.

         (b)      Except as otherwise provided for herein, Lessee agrees that it
will not make any alterations or additions to Lessee's Improvements and
Equipment until Lessee has submitted its construction and installation plans to
MATC Celular in writing, and such plans have been approved in writing by MATC
Celular. MATC Celular's approval of Lessee's construction and installation plans
shall not be unreasonably withheld, conditioned, or delayed so long as such
alterations or additions (i) together with the remaining Lessee's Improvements
and Equipment, does not exceed the structural (e.g., wind load, weight, etc.)
capacity required on the Tower for the Maximum Equipment (as defined in Section
7(a)), (ii) does not require any additional ground space, (iii) is proposed to
be located on the same height on the Tower structure as the existing Lessee's
Improvements and Equipment, and (iv) the existing Tower structure can
accommodate such additional or altered installation without requiring MATC
Celular to make aggregate capital expenditures (including all capital
expenditures made in connection with any prior structural modification of such
Tower following the date of this Agreement) with respect to such Tower in excess
of US$70,000. Lessee shall not alter any plans so approved without following the
same procedures. Lessee shall be responsible for ensuring that all external and
internal wiring and cabling installed by Lessee in the Premises is properly
grounded to the grounding ring; provided, however, that MATC Celular shall be
responsible for providing a common grounding ring. Lessee shall obtain MATC
Celular's prior written approval of such grounding plans, which approval shall
not be unreasonably withheld, conditioned or delayed. An amendment to the
applicable Site Lease shall be prepared to reflect each additional modification
to Lessee's Improvements and Equipment from time to time to which MATC Celular
has given its written consent. MATC Celular may, in its reasonable judgment,
perform or cause to be performed a structural analysis to determine the
availability of capacity at the Site for the installation or modification of any
additional equipment by Lessee at the premises. Nothing herein shall prevent
Lessee from performing such analysis for its own account; provided, however,
that Lessee shall provide a complete copy of any structural analysis that it
performs to MATC Celular

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at no cost to MATC Celular promptly upon completion of such analysis. If MATC
Celular performs such an analysis or causes one to be performed, Lessee agrees
promptly to reimburse MATC Celular for all reasonable and documented costs and
expenses incurred by MATC Celular or its vendor in the performance of such
structural analysis within thirty (30) days following receipt of an invoice from
MATC Celular. All approved work at the Site shall be performed by qualified
contractors, subject to the reasonable approval of MATC Celular. MATC Celular
and Lessee shall mutually agree, in writing, upon a list of pre-approved
contractors and subcontractors, and Lessee may retain any such pre-approved
contractor or subcontractor to perform services at the Site unless MATC Celular
has previously informed Lessee in writing of MATC Celular's reasonable desire to
remove such contractor or subcontractor from the approved list.

         4.       TERM OF SITE LEASES AND MASTER LEASE; EXTENSION PERIODS.

         (a)      The term of this Agreement shall commence on the date first
written above (the "EFFECTIVE DATE") and, unless earlier terminated in
accordance with Section 10, the terms and conditions of this Agreement shall
remain in effect with respect to each individual fully executed Site Lease for
so long thereafter as such Site Lease remains in effect pursuant to Sections
4(b).

         (b)      The initial term of each Site Lease shall commence on the
Commencement Date for such Site Lease and shall continue for ten (10) years (the
"INITIAL TERM"). The term of each Site Lease may be extended as follows: (i) the
term shall be extended automatically beyond its Initial Term for five (5) years
(the "FIRST RENEWAL TERM") unless Lessee notifies MATC Celular that it does not
wish to extend the term and such notice is given at least 90 days before the
First Renewal Term is scheduled to begin, and (ii) the term shall be further
extended beyond the First Renewal Term for five (5) years (the "SECOND RENEWAL
TERM"; each of the First and Second Renewal Terms are sometimes referred to
herein as a "RENEWAL TERM") unless Lessee notifies MATC Celular that it does not
wish to extend the term and such notice is given at least 90 days before the
Second Renewal Term is scheduled to begin. The lease term of any Site Lease
shall be the period commencing on the first day of the Initial Term and ending
on the last day of the last applicable Renewal Term, if so renewed, subject to
the provisions of Section 1(g) herein.

         5.       RENT; REIMBURSABLE COSTS.

         (a)      The rent payable to MATC Celular by Lessee for the Premises
under each Site Lease shall be equal to (i) the Base Rent (as defined in
subparagraph (b) below) in effect on the Commencement Date of the applicable
Site Lease, which shall be payable, in advance, in accordance with subparagraph
(b) below, and (ii) the Additional Rent (if any, as defined in subparagraph (c)
below), which shall be payable, in advance, in accordance with subparagraph (d)
below, both without demand. The Base Rent and Additional Rent payments shall be
effected by deposit of immediately available funds to MATC Celular at an address
to be identified to Lessee, in writing, prior to the first Commencement Date of
a Site Lease hereunder, as such address may be changed from time to time upon
written notice by MATC Celular to Lessee.

         (b)      The base rent for each Site under this Master Lease initially
shall be the amount of Two Thousand Thirty Dollars and 00/100 U.S. Cy.
(US$2,030.00) per month (the "BASE RENT"),

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plus the corresponding value added tax, if any. The parties hereto acknowledge
and agree that the Base Rent payable hereunder is premised upon Lessee's
Improvements and Equipment as specifically described in the applicable Site
Lease, but in no event to exceed the structural capacity (wind load, weight,
etc...) (including, without limitation, the dimensions) of the Maximum Equipment
(as such term is defined in Section 7 herein). The Base Rent for each Site Lease
shall be increased on July 1, 2002 and each July 1st thereafter by three percent
(3%) over the Base Rent in effect for the immediately preceding year. Such
adjustment shall become effective on each July 1st of the corresponding Site
Lease. Lessee acknowledges that Base Rent under this Master Lease is intended to
increase annually by three percent (3%). Accordingly, the initial Base Rent
under any Site Lease entered into after the date hereof shall be adjusted to
account for a three percent (3%) increase on July 1st of each year beginning on
July 1, 2002. The annual escalator provided for in this subsection (b) shall
apply to the Base Rent under this Master Lease, the Original Master Lease
Agreement and each and every Site Lease executed under this Master Lease or the
Original Master Lease Agreement. Payment of Base Rent shall commence, with
respect to each Site Lease, on the applicable Commencement Date of the relevant
Site Lease and on the first day of each month thereafter during the Term;
provided, however, that Base Rent for any fractional month or year (as
applicable) at the beginning or end of the Term shall be prorated. Lessee
acknowledges that the Base Rent payable under any Site Lease executed prior to
the date hereof pursuant to the terms of the Original Master Lease Agreement
should reflect an initial Base Rent of Two Thousand Dollars and 00/100 U.S. Cy.
(US$2,000.00) per month which was adjusted on July 1, 2001 to reflect a one and
a half percent (1.5%) increase over the Base Rent then in effect, regardless of
the Commencement Date of any applicable Site Lease and the amount actually
invoiced by MATC Celular.

         (c)      In addition to the Base Rent payable under this Section 5,
Lessee also shall pay to MATC Celular a monthly amount equal to its per capita
portion (based on the number of tenants who lease space on the applicable Tower
for a rent equal to or in excess of seventy-five percent (75%) of the Base Rent
then-payable by Lessee at the applicable Site ("PER CAPITA SHARE")) of MATC
Celular's ground rent (if any) and real property taxes (if any) payable with
respect to the applicable Site (together with the additional rent described in
Section 7(c) herein, "ADDITIONAL RENT"); provided that in the event that the
rental income (excluding service and installation fees and any pass-through
expenses, including, without limitation, ground rent, taxes, utilities, etc.)
that MATC Celular is due to collect from Other Tenants at any particular Site
exceeds Five Thousand Eight Hundred Eighty Seven United States Dollars
($5,887.00) (which amount shall be increased on July 1st of each year beginning
on July 1, 2002, by an amount equal to three percent (3%)) in any given calendar
month, Lessee shall be relieved of any obligation to pay its Per Capita Share of
the ground rent and real property taxes at such Site during that calendar month;
provided, however, if any uncollected rental income is delinquent by ninety (90)
days or more, MATC Celular may retroactively recalculate and prospectively
calculate Lessee's entitlement to an abatement of Lessee's Per Capita Share
hereunder with respect to the affected Site(s) during any such period of
delinquency by Other Tenants by excluding such uncollected rents from the
amounts MATC Celular is due to collect from Other Tenants. To the extent that
MATC Celular is required by the ground lease to pay the ground rent in United
States dollars, Lessee shall be required to pay such portion of the Additional
Rent in United States dollars. Payment of the Additional Rent set forth in this
Section 5(c) shall commence on the Commencement Date of the

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applicable Site Lease. MATC Celular will notify Lessee each time any Other
Tenant (as defined in Section 6(a)) installs its equipment on an applicable
Site.

         (d)      All Base Rent and Additional Rent due hereunder shall be paid
by Lessee to MATC Celular monthly, in advance. The first monthly payment shall
be due twenty (20) Business Days following the Commencement Date for each Site
Lease and on the fifth day of each calendar month thereafter. The Additional
Rent for any fractional month or year (as applicable) at the beginning or at the
end of the Term shall be prorated.

         (e)      In the event of any late payment of the Base Rent and/or
Additional Rent due under any Site Lease, without prejudice to any other rights
or remedies available to MATC Celular under this Master Lease or any applicable
laws, (i) Lessee shall pay interest on any unpaid portion of such Base Rent and
Additional Rent, as of the date payment was due and until payment in full, at a
rate per annum of LIBOR (as determined by Citibank N.A. in New York) plus 200
basis points, calculated on the basis of a year of three hundred and sixty (360)
days and the number of actual days elapsed, (ii) in addition, in the event that
any payment due under Site Lease remains outstanding for ninety (90) days or
more following each respective due date thereunder, Lessee shall pay, as
liquidated damages (pena convencional), an amount equivalent to one (1) payment
of one-twelfth (1/12) of the then current per annum Base Rent due for the
applicable Site Lease on the ninety-first (91st) day and at the end of each
subsequent thirty (30) days thereafter, and (iii) in addition, if Lessee is in
default on the payment of Base Rent and/or Additional Rent for six (6) months or
more with respect to ten percent (10%) or more of the Site Leases within any
Region (as defined in Section 13(a) herein) within any consecutive three (3)
month period, then in addition to any other remedies to which MATC Celular may
be entitled under this Section 5(e) and Section 10 hereof, Lessee shall
immediately prepay the Base Rent due hereunder for each Site to MATC Celular for
the remainder of the then-current term for all of the Site Leases then in effect
in such Region(s), provided, however, that upon MATC Celular's receipt of such
prepaid rent in full, Lessee shall no longer be in default with respect to the
payment of any such Base Rent during the then-current term.

         (f)      In order to secure compliance of Lessee's payment obligations
hereunder, Lessee shall deliver to MATC Celular a performance bond issued by a
Mexican bonding institution of repute, approved by MATC Celular in writing,
within twenty (20) Business Days after the Commencement Date for each Site
Lease, for an amount equal to the aggregate amount of the monthly payments of
the Base Rent and Additional Rent due under the corresponding Site Lease for the
subsequent twelve (12) month period. Lessee shall provide MATC Celular a renewal
of such bond policies yearly, no later than twenty (20) Business Days after the
anniversary of the Commencement Date, for an amount equal to the outstanding
Base Rent and Additional Rent payable through the subsequent twelve (12) month
period, as adjusted to take into account increases provided for in Section 5.
MATC Celular and Lessee acknowledge and agree that any one Affiliate of Lessee
may obtain the foregoing bond in its name for and on behalf of and for the
benefit of all or any of its Affiliates hereunder.

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         6.       RENT REDUCTIONS AND OTHER TENANTS.

         (a)      The parties hereby agree and acknowledge that premises in each
Site, other than the Premises, may be rented to third parties (each an "OTHER
TENANT") by MATC Celular, under terms and subject to the conditions established
by MATC Celular consistent with MATC Celular's obligations under Section 8
hereof. For each additional lease agreement entered into by MATC Celular with an
Other Tenant that will use premises on a Site to provide wireless
telecommunication services (including, without limitation, cellular, PCS,
wireless local loop, paging, microwave and fiber transmission), the Base Rent
payable under the applicable Site Lease will be reduced, per month and per each
such Other Tenant, by the lesser of (i) US$200 (two hundred Dollars 00/100 U.S.
Cy.) or (ii) ten percent (10%) of the monthly recurring rent paid by the Other
Tenant.

         (b)      MATC Celular shall use its commercially reasonable efforts to
deliver within twenty (20) Business Days following the end of each calendar
quarter a statement ("QUARTERLY STATEMENT") setting forth, in reasonable detail
(A) the amount of Base Rent actually paid by Lessee with respect to such
calendar quarter and the amount of Additional Rent actually paid by Lessee with
respect to such calendar quarter, (B) the amount of Base Rent due from Lessee
with respect to such calendar quarter pursuant to this Agreement (i.e., taking
into account, among other things, the amount of the rent reductions under this
Section 6) and the amount of Additional Rent due from Lessee with respect to
such calendar quarter, and (C) the net amount (the "NET AMOUNT"), if any, due to
MATC Celular or Lessee, as applicable. Within five (5) Business Days of delivery
of a Quarterly Statement the payee of the Net Amount shall provide payment
instructions to the payor specifying, among other things, whether payment of the
Net Amount is to be in U.S. Dollars or Mexican pesos. Within ten (10) Business
Days of receipt of the payment instructions, the payor shall remit the Net
Amount to the other party by wire transfer of immediately available funds in
accordance with such payment instructions. If no payment instructions are
received within five (5) Business Days of delivery of the Quarterly Statement,
the Net Amount shall be paid in US Dollars within fifteen (15) Business Days of
delivery of the Quarterly Statement by wire transfer of immediately available
funds. If payment is to be made in U.S. Dollars, it shall be made at the then
current rate at which Mexican pesos are exchangeable into U.S. Dollars as
published by Banco de Mexico in the Federal Official Gazette on the date of
payment of the Net Amount. If Lessee disputes the amounts set forth in the
Quarterly Statement, Lessee shall deliver written notice to MATC Celular setting
forth in reasonable detail the basis for such dispute. If Lessee delivers such a
dispute notice, Lessee and MATC Celular shall cooperate in good faith and use
their commercially reasonable efforts to resolve such dispute for a period of
thirty (30) days following delivery of the dispute notice. If the parties are
unable to resolve such dispute within such thirty (30) day period, the dispute
shall be resolved in accordance with Section 22.12 of this Master Lease. Absent
manifest error, any acceptance of the Net Amount by Lessee shall act as a waiver
of its right to dispute the amounts set forth in the Quarterly Statement as
provided in this Section 6(b).

         (c)      During the term of this Agreement, MATC Celular agrees to keep
all usual and proper records and books of account and all usual and proper
entries relating to this Agreement, and Lessee may conduct an audit of MATC
Celular's records applicable to (i) the calculation of the rent reductions under
this Section 6, (ii) the Per Capita Share under Section 5(c), and (iii)

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MATC Celular's compliance with the Prime Leases and legal and regulatory
requirements at each of the Sites (provided, however, that any failure by MATC
Celular to comply will not be deemed a default under this Agreement so long as
Lessee does not suffer any materially adverse consequence as a result thereof).
Any such audit will be conducted by a designated Lessee auditor or by an
independent certified public accountant selected by Lessee, and will be
conducted only with reasonable advance written request. The audit will be
conducted during regular business hours and will be conducted in such a manner
as not to interfere with MATC Celular's normal business activities. Any fees or
costs incurred by an independent certified public accountant will be paid for by
Lessee. Lessee recognizes and agrees that information learned during an audit is
confidential and that such information may be used only in further disposition
of the audit, including, without limitation, to negotiate, prosecute, and
resolve disputes.

         7.       FACILITIES; UTILITIES; ACCESS.

         (a)      Lessee, at its sole cost and expense, has the right to
install, maintain and operate on each of the Premises, Lessee's Improvements and
Equipment, which are owned by Lessee and/or any of its Affiliates, as more
specifically described in the applicable Site Lease, but in no event may
Lessee's Improvements and Equipment exceed the structural (e.g., wind load,
weight, etc.) capacity required on the Tower for twelve (12) panel Allen Telecom
ASPD-963 antennas, 12 (twelve) 1 5/8 inch coax cables, one (1) six foot diameter
Andrew solid microwave antenna and an associated 1 5/8 inch cable run, and one
(1) GPS antenna located at the same height on the antenna structure
(collectively, "MAXIMUM EQUIPMENT"). Without MATC Celular's prior written
consent, Lessee shall not have the right to relocate Lessee's Improvements and
Equipment to any location on a Site. All construction and installation work
necessary or convenient for the use of Lessee's Improvements and Equipment shall
be performed in a good and workmanlike manner. Title to Lessee's Improvements
and Equipment shall be held by Lessee. Lessee's Improvements and Equipment shall
remain Lessee's personal property and are not fixtures. Notwithstanding anything
to the contrary in this Master Lease, in the event that Lessee elects to install
less than the Maximum Equipment as of the Commencement Date, Lessee shall
reserve the right at any time during the Initial Term or any Renewal Term
thereof, to install additional improvements and equipment (or substitute
different improvements and equipment) within the Premises for no additional rent
up to the Maximum Equipment, subject to the provisions of Sections 8 and 15
herein; provided that such additional or substitute improvements and equipment
will not (i) create interference with the then-existing improvements and
equipment of any Other Tenant upon installation, or (ii) exceed the structural
capacity required on the Tower for Maximum Equipment.

         (b)      Lessee shall have the right to remove Lessee's Improvements
and Equipment under any Site Lease at any time before the expiration or earlier
termination of the applicable Site Lease so long as Lessee is not then in
default. The authorization to remove all or part of Lessee's Improvements and
Equipment prior to the termination of the Master Lease and/or the respective
Site Lease shall not be interpreted as a release of Lessee's responsibility to
perform its respective obligations under such agreements.

                                       10

<PAGE>

         (c)      If Lessee desires to install additional improvements and
equipment at any Site on space on the applicable structure outside of the
Premises or that will exceed the structural capacity (e.g., wind load, weight,
etc.) on the Tower required for the Maximum Equipment ("NEW EQUIPMENT"), MATC
Celular and Lessee shall negotiate in good faith the terms of a site lease
providing for the installation of such New Equipment on the applicable Site;
provided, however, that MATC Celular's obligation to negotiate in good faith for
the lease of additional space and/or capacity on a Site shall be conditioned
upon the existence of space on such structure which is unoccupied and not leased
under, or otherwise covered by, another agreement (or an agreement then being
negotiated by MATC Celular) permitting another third-party to use or occupy such
portion of the applicable Site ("AVAILABLE SPACE") and the obtaining of any
necessary Permits for the installation of such New Equipment. The rent payable
by Lessee for the use of additional space and/or capacity for the installation
of such New Equipment will be based upon the additional structural capacity
required for such New Equipment, pursuant to the following formula: first, the
structural capacity on a Tower required by the Maximum Equipment will be
determined based on the assumption that the Maximum Equipment is installed at
the height of Lessee's Improvements and Equipment as provided in the applicable
Site Lease; second, the structural capacity required for the New Equipment will
be determined based upon the applicable tower manufacturer's specifications and
the proposed height of such New Equipment; and third, the additional rent will
be determined based upon the structural capacity required for Maximum Equipment
(for example, assuming that the wind load factor of Maximum Equipment is 100 and
the wind load factor of such New Equipment would be 50 and the Base Rent at such
time is equal to $2,000 per month, the additional rent would be equal to $1,000
per month (50/100 times $2,000). Notwithstanding the foregoing, in the event
that the New Equipment that Lessee elects to install upon any Site pursuant to
this Section 7(c) is (i) a paging antenna, the additional rent to be paid by
Lessee shall be four hundred six dollars (US$406.00) per set of omnidirectional
and GPS antenna, or (ii) one (1) additional microwave antenna (which does not
exceed the structural capacity required for a six foot diameter Andrew solid
microwave antenna) per Site, the additional rent to be paid by Lessee shall be
two hundred three dollars (US$203.00) per microwave antenna, each subject to a
three percent (3%) increase in such additional rate on July 1st of each year
beginning on July 1, 2002. In the event that the New Equipment that Lessee
elects to install upon any applicable Site is a microwave antenna in addition to
the microwave antenna permitted by the immediately preceding sentence, the
Additional Rent to be paid by Lessee per microwave antenna shall be calculate in
accordance with the formulas contained in Exhibit E attached hereto, as such
Exhibit E may be mutually amended from time to time. All Additional Rent
pursuant to this Section 7(c) (but not pursuant to Section 5(c)) shall be
subject to increases of three percent (3%) on July 1st of each year beginning on
July 1, 2002.

         (d)      Lessee shall timely pay for the electricity used in its
operations at the rate charged by the servicing utility company. Lessee shall
draw electricity by submeter and other utilities from the existing utilities on
the Site, unless otherwise mutually agreed. Any easement necessary for such
power or other utilities will be at a location reasonably acceptable to MATC
Celular and the servicing utility company, but shall be subject to MATC
Celular's rights under the applicable Prime Lease.

                                       11

<PAGE>

         (e)      Lessee shall have the right to install or temporarily place,
as required, an emergency gasoline, butane, diesel or other fuel-powered
generator(s) on the Premises, at Lessee's sole cost and expense, and Lessee
covenants that such installation or placement and use shall be in compliance
with any applicable federal, state, or local environmental, health, fire,
community awareness, safety laws or other applicable laws or regulations, now or
hereafter enacted or promulgated by any Governmental Authority or court ruling
having jurisdiction over the relevant Site, including, without limitation, any
applicable guidelines promulgated by the environmental protection authorities.

         (f)      Lessee, Lessee's employees, agents and subcontractors may
enter on or across the Site twenty four (24) hours a day, seven (7) days a week,
at no charge, to obtain entry into the Premises for the purpose of constructing,
installing, operating, maintaining and repairing those parts of Lessee's
Improvements and Equipment as are ground based, except as otherwise expressly
provided in the Prime Lease. Lessee shall not, without prior notice to and
approval (which shall not be unreasonably withheld or delayed) from MATC
Celular, perform or arrange to be performed normally scheduled installation or
repair of Lessee's Improvements and Equipment on a Tower and MATC Celular shall
have the right to have a representative present during such installation and
repair. Any emergency installation, maintenance or repair of Lessee's
Improvements and Equipment on the Tower shall be performed only with prior
verbal notice to MATC Celular. Such access shall be in accordance with the
procedures set forth in Exhibit D attached hereto, as such Exhibit D may be
mutually amended from time to time, and such access route shall be as shown in
the applicable Site Lease. Notwithstanding the foregoing, MATC Celular reserves
the right, in its reasonable discretion, to refuse to permit any non-qualified
person or company to climb any Tower.

         8.       NON-INTERFERENCE.

         In the event that the operations of Lessee (including any subsequent
modifications or installations) under any Site Lease interfere with the then
pre-existing transmitting or receiving of radio, television, or electronic
signals by MATC Celular or Other Tenants, Lessee shall cause the interference to
be eliminated within forty-eight (48) hours, for material interference, and
fifteen (15) Business Days if otherwise measurably adverse, at no cost to MATC
Celular or Other Tenants. In the event such interference does not cease within
the applicable time period, MATC Celular may terminate the applicable Site
Lease, or shut off Lessee's Improvements and Equipment. This provision shall not
apply to test periods where the source of the interference is being determined
for purposes of suppression. In the event that, with respect to Lessee's initial
installation on any given Site or, with respect to any subsequent modification
of Lessee's Improvements and Equipment or operations, any devices installed by
MATC Celular after such modification shall interfere with Lessee's then-existing
transmission or reception, MATC Celular shall cause the interference to be
eliminated within forty-eight (48) hours, for material interference, and fifteen
(15) Business Days if otherwise measurably adverse, at no cost to Lessee.

         In the event such interference does not cease within the time periods
specified above, the parties acknowledge that continuing interference will cause
irreparable injury to the party

                                       12
<PAGE>

experiencing such interference and such party shall have all rights available
under applicable law to cause such interference to cease.

         9.       TAXES.

         As provided in Section 5(c), Lessee shall pay to MATC Celular its Per
Capita Share (as defined in Section 5(c) hereof) of all real estate taxes and
other taxes, duties or charges of similar nature imposed on the Sites. To that
effect, MATC Celular shall make the required calculations and inform Lessee the
amounts payable together with any supporting documentation. Lessee shall
reimburse MATC Celular for any increases in real property taxes that are
assessed as a direct result of Lessee's Improvements and Equipment to the Sites.
As a condition of Lessee's obligation to pay such tax increases, MATC Celular
shall provide Lessee the documentation from the relevant taxing authorities
indicating that the increase is due to Lessee's Improvements and Equipment. Any
other taxes, levies or rights imposed by any authorities as a result of the
performance of the obligations under the Original Master Lease, this Master
Lease or each Site Lease, will be borne by the corresponding party, at its sole
expense.

         10.      DEFAULT; TERMINATION.

         (a)      Either party shall be in default under an applicable Site
Lease if the party fails to perform any material duty or obligations under this
Master Lease or such Site Lease, in respect of a Site or any Premises, and does
not cure or remedy such failure to perform within twenty (20) Business Days
after receipt of written notice with respect thereto; provided, however, that if
such failure to perform shall require a longer period to cure, then such cure
period shall be extended for such time as is reasonably necessary to cure such
failure to perform (not to exceed forty-five (45) Business Days), but only so
long as such efforts to cure are commenced within ten (10) Business Days after
receipt of written notice from the other party and thereafter proceed diligently
and in good faith. Notwithstanding the foregoing, in no event shall the time
within which a party may cure a failure in the payment of money exceed a single
ten (10) Business Day period following written notice of such failure, without
extension; provided, however, that the defaulting party shall be required to pay
any overdue money after such ten (10) Business Day period has elapsed by check
and if such check is accepted and actually cashed or deposited by the
non-breaching party (so long as such check also clears), then the receipt of
such funds shall be deemed a waiver by the non-breaching party of such default.

         (b)      Upon the occurrence of a default, the non-defaulting party may
pursue any and all remedies available under applicable law and any one or more
of the following remedies, separately or concurrently or in any combination, to
the extent compatible under applicable law, without further notice or demand
whatsoever:

                  (i)      Termination of the applicable Site Lease by giving
         the defaulting party written notice of such termination, in which event
         the applicable Site Lease shall be terminated at the time designated in
         the notice; and

                  (ii)     The recovery from the defaulting party of all
         damages, costs and expenses incurred by the non-defaulting party in
         enforcing and compensating its rights and

                                       13

<PAGE>

         remedies under this Master Lease and the applicable Site Lease,
         including reasonable attorneys' fees and expenses.

         (c)      Notwithstanding the foregoing, if Lessee breaches any of its
material obligations under ten percent (10%) or more of the Site Leases then in
effect in any particular Region during any consecutive six (6) month period
during the Term, MATC Celular shall have the right to terminate this Master
Lease and any other or all of the Site Leases executed under the terms of this
Master Lease with respect to such Region; provided, however, that if MATC
Celular has previously exercised its right to accelerate the rental payments due
for the Region affected hereunder pursuant to Section 5(e) above, MATC Celular
shall not have the right to terminate the relevant Site Leases which have been
pre-paid.

         (d)      The termination of an applicable Site Lease by reason of a
party's default shall not relieve the defaulting party of any of its duties and
obligations accrued under this Master Lease in respect of such Site Lease or any
other Site Lease, prior to the effective date of such termination.

         (e)      At the expiration or termination of an applicable Site Lease
for any reason, Lessee shall surrender to MATC Celular the Premises, remove
Lessee's Improvements and Equipment, and shall restore the Premises to
substantially the same condition existing on the Commencement Date, except for
ordinary wear and tear. If Lessee fails to remove Lessee's Improvements and
Equipment as required, Lessee's Improvements and Equipment will, subject to
thirty (30) days prior written notice and subject to the rights of the Financing
Secured Parties described in Section 13(c)(i), be subject to disconnection,
removal and disposal by MATC Celular. In such event, Lessee will pay to MATC
Celular upon written demand therefor, the disconnection, removal and storage
expenses incurred by or on behalf of MATC Celular including, without limitation,
the repair of any damage to the Premises or Site caused by such removal. If
Lessee's Improvements and Equipment are not claimed by Lessee within thirty (30)
days following notice from MATC Celular to Lessee of its removal, subject to the
rights of the Financing Secured Parties described in Section 13(c)(i), MATC
Celular is hereby authorized by Lessee to take any steps necessary, subject to
any existing lien, security interest or other encumbrance, to sell all or any
portion of Lessee's Improvements and Equipment, and Lessee shall execute any
documents necessary to effect such transfer. In the event Lessee's Improvements
and Equipment remain on the Premises following termination or expiration of the
applicable Site Lease (even if it has been disconnected), Lessee shall pay to
MATC Celular holdover rent equal to one hundred and twenty-five percent (125%)
of the then effective Base Rent, pro-rated from the date of termination to the
date Lessee's Improvements and Equipment are removed from the Premises by
Lessee. The parties hereby specifically acknowledge that MATC Celular will be
under no obligation to repay Lessee for any construction, improvements or work
performed on a Site by Lessee, and Lessee hereby waives the provisions of
articles 2423 and 2424 of the Federal Civil Code and the applicable provisions
of the Civil Codes of the jurisdictions in which any Site is located.
Notwithstanding anything to the contrary herein, the notice requirements
outlined in this Section 10(e) shall not apply to the extent that they conflict
with the provisions of the applicable Prime Lease pursuant to its termination or
expiration.

         (f)      [INTENTIONALLY OMITTED]

                                       14

<PAGE>

         (g)      Subject to Section 10(j), upon no less than thirty (30) days
prior written notice (unless a lesser period of time is otherwise required by
law), either party hereto may terminate the applicable Site Lease without any
further obligation by either party to the other if any law, ordinance,
regulation or directive of any governmental or regulatory authority hereinafter
enacted or ordered prohibits Lessee's or MATC Celular's use of the Premises so
long as such governmental action is not the result of any action or inaction by
the terminating party.

         (h)      MATC Celular will provide Lessee with a copy of any notice of
default received by MATC Celular under any Prime Lease in the event that MATC
Celular does not intend to or can not cure any such default during the
applicable cure period provided for in the Prime Lease or of any notice,
complaint, order or decree that will (or could) adversely affect Lessee's
ability to operate its wireless communications facility from the Site or will
(or could) adversely affect any right or remedy of Lessee hereunder. Any failure
by MATC Celular to deliver notice pursuant to this Section shall not be deemed a
default under this Agreement so long as Lessee does not suffer any materially
adverse consequence as a result thereof.

         (i)      Notwithstanding anything to the contrary in this Agreement, in
the event that MATC Celular fails to comply with the provisions of a Prime
Lease, any Governmental Requirements (other than failure to obtain Tower Site
Permits that Lessee or its affiliates were required to obtain prior to Closing),
or its maintenance or repair obligations hereunder and Lessee's rights hereunder
shall (or could) be materially and adversely affected by a failure to comply,
Lessee (in addition to any other rights and remedies it may be entitled to
hereunder) will be authorized, following no less than five (5) Business Days
prior written notice to MATC Celular (unless during such period MATC Celular
diligently commences and pursues the cure of such failure), to pay any
reasonable amount required to cure such failure or, if applicable, commence and
prosecute any and all reasonable action or actions necessary to cure such
failure as may be available to MATC Celular. Following any such payment by
Lessee, Lessee will be entitled to withhold the full amount thereof from
installments of rent or other payments next owing under this Agreement until
such amount and charge have been fully credited. Any dispute as to the
obligation to pay any such amount or pursue any specific action pursuant to this
Section 10(i), will be resolved in accordance with Section 22 hereof.

         (j)      In the event that a tower structure upon which the Premises
are located at any Site must be removed, dismantled or otherwise becomes
unusable because the applicable Tower Site Permits for a Site were required to
be obtained by Lessee or its Affiliates prior to the Closing (as defined in the
Purchase Agreement) of such Site, but were not obtained by Lessee or such
Affiliates, then (i) the associated Site Lease shall be deemed to have been
terminated contemporaneously therewith, (ii) Lessee shall promptly indemnify
MATC Celular, which indemnification shall be paid (A) if Base Rent is being paid
annually, then annually in advance on the anniversary of the applicable
Commencement Date, beginning on the date of such deemed termination and ending
on the nine year anniversary of the applicable Commencement Date (i.e., payment
shall be through the remainder of the Initial Term), or (B) if Base Rent is
being paid monthly, then monthly in advance on the first of each month beginning
on the date of such deemed termination and ending on the month immediately prior
to the ten (10) year anniversary of the Commencement Date (i.e., payment shall
be through the remainder of the Initial Term); in each case in an amount equal
to the rent that would have been payable to MATC Celular under

                                       15

<PAGE>

the applicable Site Lease. To the extent that Lessee has prepaid rent
corresponding to any periods after the deemed termination, such prepaid rent
shall count toward Lessee's indemnity obligation described in this Section
10(j). The Indemnification described in this Section 10(j) shall be in addition
to any other indemnification provided for in this Section 10 or any other
section of this Agreement and Lessee further waives any right to claim such
event as a force majeure event under the applicable provisions of the Federal
Civil Code and its corresponding articles of the Civil Codes for the Federal
District and the States of Mexico.

         11.      EXPROPRIATION.

         If the whole or any substantial part of a Site shall be taken by any
public authority under the power of eminent domain (expropiacion) so as to
materially interfere with Lessee's use and occupancy, then the Site Lease shall
terminate as to such Site so taken. Any Base Rent covering the period after the
effective date of termination paid in advance shall be refunded to Lessee within
thirty (30) days of Lessee's written demand.

         12.      INSURANCE.

         (a)      Each Party shall carry during the term of each Site Lease, at
its own cost and expense, the following insurance with respect to the Sites and
the Premises: (i) "All Risk" property insurance which insures the insuring
party's property for its full replacement cost; and (ii) comprehensive general
liability insurance with a commercial general liability endorsement having a
minimum limit of liability of US$1,000,000.00 (one million Dollars 00/100 U.S.
Cy.) with a combined limit for bodily injury and/or property damage for any one
occurrence, and (iii) excess/umbrella coverage of US$5,000,000.00 (five million
Dollars 00/100 U.S. Cy.) MATC Celular agrees to use its reasonable best efforts
to require all Other Tenants who execute lease agreements with MATC Celular on
or after the date first written above to maintain insurance coverage comparable
(based on such Other Tenant's equipment installation and use of a Site) to the
coverage limits set forth in this Section 12(a).

         (b)      Each Party shall name the other as an additional insured (in
the case of Lessee, such rights of MATC Celular to be subject to the rights of
the Financing Secured Parties described in Section 13(c)(i)) under its liability
policy and require its insurance company to endeavor to give at least thirty
(30) days' written notice of termination or cancellation of the policy to the
additional insured. A certificate of such insurance, together with such
endorsement, shall be delivered to the additional insured within thirty (30)
days from the Commencement Date for each Site Lease and before the expiration of
any term thereof, from a licensed insurance company. All insurance certificates
must contain an undertaking by the agents or brokers to notify the other party
in writing not less than thirty (30) days before any material change, reduction
in coverage, cancellation or termination of the insurance.

         (c)      Lessee shall cause any contractor retained by Lessee to
maintain in full force and effect during the term of any maintenance, work or
repairs performed on Lessee's behalf at any Site, insurance satisfying the
coverage requirements described in Section 12(a) and to deliver, prior to the
commencement of such work, an insurance certificate naming MATC Celular as an
additional insured. Lessee shall be solely responsible and liable to MATC
Celular for Lessee's

                                       16

<PAGE>

failure to obtain or deliver to MATC Celular the required insurance certificates
from Lessee's approved contractor.

         13.      ASSIGNMENT.

         (a)      This Master Lease or any Site Lease may be sold, assigned or
transferred, in whole or in part, by MATC Celular (i) to any subsidiary and/or
affiliate of MATC Celular; (ii) in the event of a sale, assignment or transfer
of all or substantially all of MATC Celular's assets or equity interests in one
or a series of related transactions; (iii) in the event of a sale, assignment or
transfer of all or substantially all of MATC Celular's assets located within a
particular Mexican Region (as such regions are commonly defined with respect to
communication services as of the date of the execution of this Master Lease and
hereinafter referred to as a "REGION(S)"); and (iv) pursuant to any merger,
stock transfer, sale of all or substantially all of the assets of or other
corporate reorganization involving any of MATC Celular's parent companies;
provided, however, that, except in connection with a merger, stock transfer,
sale of all or substantially all of the assets of or other corporate
reorganization involving American Tower Corporation, MATC Celular's ultimate
parent entity (or its successor-in-interest), MATC Celular may in no event
assign all or any part of this Master Lease or any Site Lease to any of the
following of Lessee's competitors: Telcel, Pegaso, or Unefon (or any of their
successors-in-interest), or any other person domiciled in Mexico who is an
Affiliate of such competitor as of the date of this Agreement. Any other
assignment of this Master Lease or any Site Lease shall require the prior
written consent of Lessee, which consent shall not be unreasonably withheld,
conditioned or delayed.

         (b)      This Master Lease or any Site Lease may not be sold, assigned
or transferred, in whole or in part, by Lessee without the prior approval or
consent of MATC Celular; provided, however, that notwithstanding anything to the
contrary contained herein, (i) Lessee may sublease any space on the Premises,
transfer any of its rights and/or obligations under this Master Lease, Lessee's
Improvements and Equipment and/or any Site Lease to any subsidiary and/or
Affiliate whose ownership or voting percentage is not modified to less than
forty-five percent (45%) of the current ownership or voting percentage by any
act or series of acts subsequent to the assignment that may cause Lessee to lose
such percentage within two (2) years from the date of the assignment, provided
that the respective permitted sublessee or assignee must agree in writing,
before taking possession of the subleased Premises, to be bound by all the terms
and conditions of this Master Lease and the applicable Site Lease; (ii) in the
event that such sale, assignment or transfer is associated with the sale of all
or substantially all of Lessee's assets located within a particular Region, MATC
Celular may not unreasonably withhold, condition, or delay such consent; (iii)
Lessee may sell, assign or transfer its rights under this Master Lease or any
Site Lease pursuant to any merger, stock transfer, sale of all or substantially
all of the assets of or other corporate reorganization involving any of Lessee's
parent companies; and (iv) Lessee may grant a security interest in this Master
Lease in favor of the Financing Secured Parties as contemplated by Section
13(c)(i). In no event may Lessee sublease, sublicense, or permit shared use of
the Premises by any party other than an Affiliate of Lessee in accordance with
subsection 13(b)(i) herein; provided, however, that in the event that the
applicable antenna structure is fully loaded and can not be structurally
modified to accommodate any additional equipment, Lessee

                                       17

<PAGE>

may sublease or sublicense the Premises to a third party with the prior written
consent of MATC Celular, which consent shall not be unreasonably withheld or
delayed.

         (c)      Notwithstanding the foregoing, Lessee hereby acknowledges and
consents to the security interests to be granted by MATC Celular in this Master
Lease, each Site Lease and any other rights, obligations or interests hereunder
or thereunder in favor of Toronto Dominion (Texas), Inc., as Administrative
Agent (and its successors and assigns) for the benefit of the Lenders (as
defined therein) under the Credit Agreement dated as of December 22, 2000, as
may be amended or supplemented from time to time, with American Tower
Corporation de Mexico, S. de R.L. de C.V., MATC Holdings, Mexico, S. de R.L. de
C.V., MATC TV, S. de R.L. de C.V. and MATC Celular and the other Subsidiaries
(as defined therein) identified in such agreement as "Guarantors" and undertakes
to, upon receipt of a default notice, without verification, investigation or
inquiry as to the authenticity of such default notice, cease delivering to MATC
Celular, any and all payments on account of the secured property and shall
henceforth deliver all such payments to the secured party, as pledgee of the
corresponding amounts, by crediting the amount of such payments to the account
indicated in the default notice. MATC Celular, in turn, hereby acknowledges and
consents to the security interests granted by Lessee or its affiliates in this
Master Lease, any Site Lease and any of Lessee's Improvements and Equipment in
favor of (i) BNP Paribas, as Collateral Agent (and its successors and assigns)
for the benefit of (A) the Export-Import Bank of the United States and the
Lender under a Credit Agreement dated as of March 3, 1999, as amended, with
Grupo Iusacell, S.A. de C.V. (now Grupo Iusacell Celular, S.A. de C.V.) as
borrower, and (B) the Commercial Lenders under a Commercial Loan Agreement dated
as of March 3, 1999, as amended, with Grupo Iusacell, S.A. de C.V. (now Grupo
Iusacell Celular, S.A. de C.V.) as borrower (said Collateral Agent, Lender,
Commercial Lenders and Export-Import Bank of the United States, collectively,
"Eximbank Financing Secured Parties") pursuant to the mortgage contained in
notarial instrument number 8825, executed on April 15, 1999, as amended, before
Mr. Francisco I. Hugues Velez, notary public number 212 of Mexico, Federal
District, acting in the notarial protocol of Mr. Jose Eugenio Castaneda
Escobedo, notary public number 211 of Mexico, Federal District, recorded with
the Public Registry of Commerce of the Federal District on April 26, 1999, under
Commercial Folios number 126,502, 129,279, 132,047, 168,528 and 177,150 and (ii)
The Chase Manhattan Bank ("Chase") as lender and as collateral agent and
administrative agent for the lenders (the "Chase Lenders") listed in the Credit
Agreement dated as of July 25, 1997, as amended, entered into with Grupo
Iusacell, S.A. de C.V., as borrower which security interests were perfected
under a Mortgage Agreement dated July 25, 1997, which was notarized under
notarial deed number 5,114 dated December 1, 1997 with the Public Registry of
Commerce of Mexico City, Federal District under commercial files no. 129,279;
126,502; 168,528; 177,150; 120,042; and 132,047 and amended under the First
Amendment to the Mortgage notarized under notarial deed number 8,824, dated
April 15, 1999 and registered under the same commercial files (the Eximbank
Financing Secured Parties, Chase and the Chase Lenders are collectively referred
to as the "Financing Secured Parties"). Lessee may, upon prior written notice to
MATC Celular, mortgage or grant a security interest in Lessee's Improvements and
Equipment to any bona fide unaffiliated institutional lender in connection with
any bona fide financing by Lessee, and may assign its rights to Lessee's
Improvements and Equipment to any such mortgagees or holders of security
interests including their successors or assigns (hereinafter, with the Financing
Secured Parties, collectively referred

                                       18

<PAGE>

to as "LESSEE MORTGAGEES"). In such event, MATC Celular shall execute such
consent to leasehold financing as may reasonably be required by Lessee
Mortgagees, in which MATC Celular will agree to notify Lessee and the Lessee
Mortgagees simultaneously of any default by Lessee and to give Lessee Mortgagees
the same right to cure any default as Lessee except that the cure period for any
Lessee Mortgagee shall not be less than ten (10) days after receipt of the
default notice.

         14.      WARRANTY OF TITLE AND QUIET ENJOYMENT; COMPLIANCE WITH LAWS.

         (a)      MATC Celular warrants that: (i) MATC Celular owns or leases
the Site and the Tower located thereon (if any) and will have rights of access
thereto; (ii) MATC Celular has full right to make and perform this Master Lease;
and (iii) MATC Celular covenants and agrees with Lessee that, according to
article 2412 of the Federal Civil Code and the applicable provisions of the
Civil Codes of the jurisdictions where any Site is located, upon Lessee paying
the Base Rent and Additional Rent and observing and performing all the material
terms, covenants and conditions on Lessee's part to be observed and performed,
Lessee may peacefully and quietly have, hold and enjoy possession and use of
each of the Premises. Notwithstanding anything to the contrary herein, (i) no
representation, warranty or covenant made by MATC Celular in this Master Lease
shall be enforceable by Lessee against MATC Celular (or be deemed breached by
MATC Celular hereunder) in the event that such representation, warranty or
covenant (x) is contrary to any disclosure made by Lessee to MATC Celular
pursuant to the Purchase Agreement, or (y) relates to or existed during any
period of time prior to the Closing, and (ii) any representation, warranty or
covenant made by MATC Celular in this Master Lease shall be subject to and
limited by any similar representation, warranty, and covenant made by Lessee to
MATC Celular under the Purchase Agreement.

         (b)      In the performance by each party to this Agreement of its
respective obligations hereunder, the parties recognize and acknowledge that
each party hereto shall be responsible for the personnel it employs to perform
its respective obligations hereunder, including, without limitation, their
ordinary and extraordinary salaries, vacations, Christmas bonus (aguinaldo),
seniority payments (prima de antiguedad), disability payments, severance
payments, contributions to the IMSS and INFONAVIT and any other existing
obligation derived from the Federal Labor Law (Ley Federal de Trabajo)
(collectively, "LABOR OBLIGATIONS"). Each party shall have no responsibility for
the other party's Labor Obligations or to the other party's personnel or
otherwise, and each party agrees to indemnify, defend and hold harmless the
other party and its respective Affiliates, and their directors, officers and
employees, from and against all Losses based upon any claim arising out of Labor
Obligations. In the performance by the parties of their respective obligations
under this Agreement, each of MATC Celular and Lessee agree to comply with any
and all applicable laws of Mexico and, as applicable, the United States. Without
limiting the generality of the foregoing, MATC Celular and Lessee each agree, in
the performance of their respective obligations hereunder, to comply with the
provisions of the Foreign Corrupt Practices Act of the United States.

         (c)      Notwithstanding the provisions of this Section 14, any Site
Lease hereunder may be terminated, without any further obligation by either
party to the other, by Lessee, from the period beginning on the date first
written above and ending ten (10) years thereafter

                                       19

<PAGE>

("TERMINATION PERIOD"), in the event that a man-made obstruction constructed
subsequent to Lessee's installation (or later modification) adversely affects
Lessee's RF requirements with respect to the operation of such affected
equipment; provided, however, that in no event may Lessee terminate more than an
aggregate of five percent (5%) of all of the Site Leases executed by Lessee
hereunder during the Termination Period pursuant to this Section 14(c).

         15.      MAINTENANCE AND REPAIRS.

         (a)      Lessee shall perform all repairs necessary or appropriate to
keep Lessee's Improvements and Equipment on or about the Premises or located on
any appurtenant rights-of-way or access to the Premises in good and tenantable
condition. Damage to Lessee's Improvements and Equipment resulting from the acts
or omissions of MATC Celular shall be repaired by MATC Celular, at MATC
Celular's cost and expense unless otherwise provided herein.

         (b)      MATC Celular, at MATC Celular's sole cost and expense, shall
maintain the Sites and its improvements thereto in good order and repair, except
acts resulting from an act of God or force majeure (caso fortuito o fuerza
mayor) which shall be repaired by MATC Celular as promptly as is practical under
the circumstances; provided, however, that if Lessee's ability to provide
service to its customers through Lessee's Improvements and Equipment is
negatively affected, MATC Celular shall commence the repair of the facilities
within twenty-four (24) hours and shall complete such repairs within the time
period reasonably necessary to effect such repairs under the circumstances
following written notice from Lessee thereof. Damage resulting from the acts or
omissions of Lessee shall be repaired by Lessee, at Lessee's cost and expense
unless otherwise provided herein.

         16.      MISCELLANEOUS.

         (a)      Entire Agreement. This Master Lease, the applicable Site
Leases and the Purchase Agreement and all schedules and exhibits hereto or
thereto constitute the entire agreement and understanding between the parties,
and supersedes all offers, negotiations and other agreements concerning the
subject matter contained herein. Any amendments to this Master Lease or any Site
Lease must be in writing and executed by both parties.

         (b)      Severability. If any provision of this Master Lease is invalid
or unenforceable with respect to any party, the remainder of this Master Lease
or the application of such provision to persons other than those as to whom it
is held invalid or unenforceable, shall not be affected and each provision of
this Master Lease shall be valid and enforceable to the fullest extent permitted
by law.

         (c)      Binding Effect. This Master Lease shall be binding on and
inure to the benefit of the successors and permitted assignees of the respective
parties.

         (d)      Notices. Any notice or demand required to be given herein
shall be made by recognized overnight courier to the address of the respective
parties set forth below:

                                       20

<PAGE>

         GRUPO IUSACELL:          Grupo Iusacell Celular, S.A. de C.V.,
                                  Prol. Paseo da la Reforma 1236, 4th Floor
                                  Col. Santa Fe, 05348 Mexico, D.F.
                                  Attention: Vice President/Technical Operations
                                  Fax No.: (011) (525) 109-5407

         IUSACELL ARRENDADORA, S.A. DE C.V.:

                                  Prol. Paseo de la Reforma 1236, 4th Floor
                                  Col. Santa Fe, 05348 Mexico, D.F.
                                  Attention: Vice President/Technical Operations
                                  Fax No.:  (011) (525) 55-109-5407

         With a copy to:          Grupo Iusacell Celular, S.A. de C.V.
                                  Prol. Paseo da la Reforma 1236, PH
                                  Col. Santa Fe, 05348 Mexico, D.F.
                                  Attention: General Counsel
                                  Fax No.:  (011) (525) 55-109-5772

         MATC CELULAR:            MATC Celular, S. de R.L. de C.V.
                                  Paseo de la Reforma No. 350
                                  Col. Lomas de Chapultepec
                                  11000, Mexico, D.F.
                                  Attn: Kevin Corrigan
                                  Fax: (011) (525) 55-240-2026

         With a copy to:          American Tower Corporation
                                  116 Huntington Avenue
                                  Boston, MA  02116
                                  Attention: General Counsel
                                  Fax No.: (617) 375-7575

                                  - and-

                                  American Tower International
                                  Galleria 75 Office Park, Suite 205
                                  3200 Cobb Galleria Parkway
                                  Atlanta, Georgia 30339
                                  Attention: Dan Brooks
                                  Fax No.: (770) 952-4999

         MATC Celular or Lessee may from time to time designate any other
address for this purpose by written notice to the other party. All notices
hereunder shall be deemed received upon actual receipt.

                                       21

<PAGE>

         (e)      Governing Law. This Master Lease shall be governed, to the
extent applicable, by the Federal Civil Code and other applicable federal laws
of the United Mexican States ("MEXICO"). The Site Leases shall be governed by
the laws of the jurisdiction on which the corresponding Sites are located, as
specified in each Site Lease.

         (f)      [INTENTIONALLY OMITTED]

         (g)      Counterparts. This Master Lease, each Site Lease and all
Exhibits to this Master Lease or any Site Lease may be executed in as many
counterparts as the parties deem necessary, each of which shall be deemed an
original, and all of such counterparts together shall constitute one and the
same instrument. This Master Lease and any Site Lease may be executed in
triplicate counterparts, each of which shall be deemed an original.

         (h)      Language. This Master Lease is executed and each Site Lease
will be executed in the English language; provided, however, that the parties
hereto hereby irrevocably agree and accept that the Spanish translation of this
Agreement attached hereto as Exhibit C, is a true, accurate and complete
translation of this Agreement that shall be used in the event that any party
hereto brings a legal action or proceeding with respect to this Agreement and
the parties hereto hereby waive any right to challenge the validity,
truthfulness, accuracy or completeness of such Spanish translation.

         17.      TOWER MARKING AND LIGHTING REQUIREMENTS.

         For each Site, MATC Celular shall be responsible for compliance with
all marking and lighting requirements under applicable laws and regulations in
Mexico, provided that if the requirement for compliance results from Lessee's
Improvements and Equipment, Lessee shall pay for the reasonable costs and
expenses therefor.

         18.      INDEMNITY.

         (a)      Each party hereto ("INDEMNIFYING PARTY") agrees to compensate
the other party for damages and to defend, indemnify and to hold the other party
harmless from all claims (including reasonable attorneys' fees, costs and
expenses of defending against such claims) incurred and arising from the
negligent acts or omissions of the Indemnifying Party or its agents, employees,
engineers, contractors, subcontractors, or invitees in or about the Premises or
arising from the Indemnifying Party's default pursuant to this Master Lease or
the applicable Site Lease. Except as otherwise specifically provided herein to
the contrary, it is understood and agreed that all property kept, installed,
stored, or maintained in or upon the Premises by Lessee shall be so installed,
kept, stored, or maintained at Lessee's risk. Neither party hereto shall be
responsible for any loss or damage to equipment owned by the other party which
might result from tornadoes, lightning, wind storms, hail, flying debris, or
other acts of God (caso fortuito o fuerza mayor). The indemnities described in
this Section shall survive termination of this Master Lease or the applicable
Site Lease.

         (b)      Notwithstanding any provision of this Master Lease to the
contrary (other than Section 5 hereof), each party hereby waives the right to
recover consequential (including lost

                                       22

<PAGE>

profits), punitive, exemplary and similar damages and the multiplied portion of
damages to the extent provided under applicable law, except to the extent such
damages are suffered by such party in connection with an action initiated by a
third party in which case the damages paid to such third party shall be deemed
compensatory damages.

         (c)      Notwithstanding anything to the contrary contained in this
Master Lease, no party may be granted indemnity under this Master Lease if it
has already received indemnity for the same claim under the Purchase Agreement.

         19.      HAZARDOUS SUBSTANCES.

         Lessee agrees that it will not use, generate, store or dispose of any
hazardous material on, under, about or within the Sites in violation of any law
or regulation. MATC Celular represents, warrants and agrees (i) that neither
MATC Celular nor, to MATC Celular's knowledge, any third party has used,
generated, stored or disposed of, or permitted the use, generation, storage or
disposal of, any hazardous material on, under, about or within the Sites in
violation of any law of regulation, unless otherwise disclosed in the applicable
Site Lease and (ii) that MATC Celular will not generate, store or dispose of any
hazardous material on, under, about or within the Sites in violation of any law
or regulation. MATC Celular and Lessee each agree to defend, indemnify and hold
harmless the other party and the other party's partners, affiliates, agents and
employees against any and all losses, liabilities, claims and/or costs
(including reasonable attorneys' fees and costs) arising from any breach of any
representation, warranty or agreement contained in this Section 19. As used in
this Section 19, "HAZARDOUS MATERIAL" shall mean petroleum or any petroleum
product, asbestos, and/or any substance, chemical or waste that is identified as
hazardous, toxic or dangerous in any applicable federal, state or local law or
regulation. This Section shall survive the termination of this Master Lease.

         20.      REPLACEMENT OR RECONSTRUCTION OF TOWER BY MATC CELULAR.

         Notwithstanding anything to the contrary contained herein, Lessee
acknowledges and agrees that MATC Celular reserves the right to replace or
rebuild an existing structure or the top of any structure upon no less than ten
(10) days prior written notice to Lessee, provided, however, that in the event
of such replacement, MATC Celular shall provide Lessee with suitable space at
the Site during the construction period to permit the continued operation of
Lessee's Improvements and Equipment and MATC Celular shall be solely responsible
for the costs associated with removing and re-installing the Lessee's
Improvements and Equipment on the replacement structure. MATC Celular also
expressly reserves the right to erect one or more Towers on the Site, subject to
MATC Celular's obligations to Lessee pursuant to Section 8 of this Master Lease.
In no event shall Lessee's Base Rent be abated in any manner during any period
of construction of the Tower or candelabra so long as Lessee is capable of
continuing to operate its equipment from a temporary location on the Site.
Lessee acknowledges and agrees that it will reasonably cooperate with MATC
Celular in any actions, filings, or permits which may be required for MATC
Celular to exercise its rights under this Section 20. In the event that the
replacement space provided to Lessee fails to meet Lessee's RF standards, Lessee
shall reserve the right to terminate the applicable Site Lease upon thirty (30)
days notice to MATC Celular without any further obligation of either party to
the other hereunder.

                                       23

<PAGE>

         21.      CONFIDENTIALITY.

         The parties agree to hold the economic terms and conditions of this
Agreement in strict confidence, and shall bind its employees, affiliates,
advisors, representatives and agents to keep such economic terms in strict
confidence, and not to make any disclosure with respect thereto, publicly or
privately, other than as is jointly agreed to by the parties or as is required
by applicable law (of any applicable country), including the rules and
regulations of the Mexican National Banking and Securities Commission, the
Securities and Exchange Commission, and the stock exchange rules or regulations.
If a public statement by either party is determined to be required by law or
stock exchange rules or regulations, the other party shall have the right to
review and comment on such statement prior to its release to the extent
practicable. Except as otherwise provided above, without the prior written
consent of the other party, no party shall at any time disclose any such
economic terms to any third party not bound by the confidential duty. The
provisions contained herein shall survive termination of this Agreement and
shall remain in full force and effect for a term of five (5) years after
termination of this Agreement.

         22.      DISPUTE RESOLUTION.

         SECTION 22.1 AGREEMENT TO ARBITRATE. Any and all claims, counterclaims,
demands, causes of action, disputes, controversies, and other matters in
question arising out of or relating to this Agreement, or the alleged breach
hereof, or in any way relating to the subject matter of this Agreement or the
relationship between the Parties created by this Agreement (all of which are
referred to herein as "CLAIMS"), between two or more parties (each a "DISPUTING
PARTY") shall be resolved by binding arbitration, regardless of whether such
Claims (a) allegedly are extra-contractual in nature, (b) sound in contract,
tort, or otherwise, (c) are provided for by statute or otherwise, or (d) seek
damages or any other relief; provided, however, that each Party expressly waives
any right to any form of damages in excess of compensatory damages, and agrees
not to seek such damages in any forum, as a result of any dispute, controversy
or claim arising out of, relating to or in connection with this Agreement,
including, without limitation, any dispute regarding its validity or
termination, or the performance or breach thereof, and each party further agrees
that the arbitrators are divested of, and will not have, jurisdiction or the
authority to award any form of damages in excess of compensatory damages.
Without limiting the authority conferred on the arbitrators by this Agreement
and the ICC Rules, the arbitrators shall have the authority to award specific
performance. No Claim shall be submitted to arbitration until sixty (60) days
have passed (without mutual agreement having been reached) following the first
written notice from a Disputing Party to the other Disputing Parties that sets
forth the subject matter of the Claim and that states that it is being given
pursuant to this Section 22.1. Each Disputing Party shall, if requested by
another Disputing Party, select and appoint a senior executive (not concerned
with the day-to-day performance of the appointor's obligations under this
Agreement) to serve on a panel seeking to reach mutual agreement with respect to
the applicable Claim. Each such appointment shall be made by the giving of
notice by the appointor to the other Disputing Parties within ten (10) Business
Days of the request for the appointment. The appointees shall meet and shall
endeavor to reach such mutual agreement as soon as practicable.

                                       24

<PAGE>

         SECTION 22.2 APPOINTMENT OF ARBITRATORS. If no such mutual agreement
has been reached within such sixty (60) day period, then any Disputing Party may
refer the claim to arbitration under the following provisions:

         (a)      To refer a claim to arbitration, a Disputing Party must
provide notice to the ICC and the other Disputing Parties stating (i) a general
description of the Claim and (ii) that the Claim is being referred to
arbitration under this Section 22.

         (b)      The arbitration panel shall consist of three neutral
arbitrators. Each Disputing Party shall appoint one arbitrator, obtain its
appointee's acceptance of such appointment, and deliver written notification of
such appointment and acceptance to the other Disputing Party within thirty (30)
days after delivery of the notice described in Section 22.2(a) hereof. In the
event a Disputing Party fails to appoint an arbitrator or deliver notification
of such appointment to the other Disputing Party within this time period, upon
request of either Disputing Party, such arbitrator shall instead be appointed by
the ICC within thirty (30) days of receiving such request. The two arbitrators
appointed in accordance with the above provisions shall appoint the third
arbitrator who shall be an attorney licensed to practice law in Mexico, obtain
the appointee's acceptance of such appointment and notify the Disputing Parties
in writing of such appointment and acceptance within thirty (30) days of their
appointment. If the first two appointed arbitrators fail to appoint a third
arbitrator or notify the Disputing Parties of that appointment within this time
period, then, upon request of either Disputing Party, the third arbitrator shall
be appointed by the ICC within thirty (30) days of receiving such request. The
third arbitrator shall serve as chairman of the arbitration tribunal.

         SECTION 22.3 AUTHORITY OF THE ARBITRATORS. The validity, construction,
and interpretation of this agreement to arbitrate, and all procedural aspects of
the arbitration conducted pursuant to this agreement to arbitrate, including,
but not limited to, the determination of the issues that are subject to
arbitration (i.e., arbitrability), the scope of the arbitrable issues,
allegations of "fraud in the inducement" to enter into this agreement to
arbitrate, allegations of waiver, delay or other defenses to arbitrability, the
appropriateness of summary judgment and the rules governing the conduct of the
arbitration (including the time for filing an answer, the time for the filing of
counterclaims, the times for amending the pleadings, the specificity of the
pleadings, the extent and scope of discovery, the issuance of subpoenas, the
times for the designation of experts, whether the arbitration is to be stayed
pending resolution of related litigation involving third parties not bound by
this agreement to arbitrate, the receipt of evidence, and the like) shall be
decided by the arbitrators. The arbitrators shall have the authority to assess
the costs and expenses of the arbitration proceeding (including the arbitrators'
fees and expenses) against one or more of the Disputing Parties in whatever
manner or allocation the arbitrators deem appropriate, provided that each
Disputing Party shall bear its own attorneys' fees, and the arbitrators shall
have no authority to award attorneys' fees.

         SECTION 22.4 PLACE OF ARBITRATION. The arbitration proceeding shall be
conducted in Mexico City, Mexico.

         SECTION 22.5 CONDUCT OF THE ARBITRATION. It is the intent of the
Parties that, barring extraordinary circumstances, the arbitration proceedings
shall be concluded within one hundred

                                       25

<PAGE>

eighty (180) days from the date the arbitrators are appointed. The Parties may
agree to extend this time limit or the arbitrators may do so in their discretion
if they determine that the interest of justice so requires. The arbitrators
shall use their best efforts to issue the Award within sixty (60) days after
closure of the proceedings. Failure to adhere to these time limits shall not be
a basis for challenging the award. The arbitration proceedings and the award or
decision ("AWARD") of the arbitrators shall be in English. Notwithstanding the
foregoing, either Disputing Party may submit testimony or documentary evidence
in the Spanish language, provided that the Disputing Party submitting such
evidence, at its own cost, also furnishes to the other party a translation into
the English language.

         SECTION 22.6 ICC RULES. The arbitration shall be conducted under the
ICC Rules, except as they may be modified in this Section 22 or by agreement of
the Parties.

         SECTION 22.7 PAYMENT OF AWARD. Each Disputing Party against which the
arbitrators' Award assesses a monetary obligation shall pay that obligation on
or before the 30th day following the Award or such other date as the Award may
provide, which Award shall be payable in cash in dollars unless the Award
specifies a different currency.

         SECTION 22.8 FINALITY OF THE ARBITRATORS' AWARD. The arbitrators' Award
shall, as between the Disputing Parties and those in privity with them, be final
and entitled to all of the protections and benefits of a final judgment, e.g.,
res judicata (claim preclusion) and collateral estoppel (issue preclusion), as
to all Claims, including compulsory counterclaims, that were or could have been
presented to the arbitrators. The arbitrators' Award shall not be reviewable by
or appealable to any court.

         SECTION 22.9 USE OF THE COURTS. It is the intent of the Parties that
the arbitration proceeding shall be conducted expeditiously, without initial
recourse to the courts and without interlocutory appeals of the arbitrators'
decisions to the courts. However, by agreeing to arbitration, the Parties do not
intend to deprive any court with jurisdiction of its ability to issue a
preliminary injunction, attachment or other form of provisional remedy in aid of
the arbitration and a request for such provisional remedies by a Disputing Party
to a court shall not be deemed a waiver of the agreement to arbitrate contained
in this Section 22. Any court order compelling arbitration shall require that
the arbitration proceedings take place in Mexico City, Mexico as specified
above. The Disputing Parties may apply to any court having jurisdiction for
orders requiring witnesses to obey subpoenas issued by the arbitrators.
Moreover, any and all of the arbitrators' orders and decisions may be enforced
if necessary by any court having jurisdiction. The arbitrators' Award may be
confirmed in, and judgment upon the Award entered by, any court having
jurisdiction.

         SECTION 22.10 CONFIDENTIALITY. Except as may be required by applicable
law or court order, the Disputing Parties shall maintain confidentiality as to
all aspects of the arbitration, including its existence and results, except that
nothing herein shall prevent any Disputing Party from disclosing information
regarding the arbitration for purposes of enforcing the Award or in any court
proceeding involving the Disputing Parties. The Parties further agree to obtain
the arbitrators' agreement to preserve the confidentiality of the arbitration.
However, a violation of

                                       26

<PAGE>

this covenant shall not affect the enforceability of this agreement to arbitrate
or of the arbitrators' Award.

         SECTION 22.11 ARBITRATION PROVISION ENFORCEABLE. A Disputing Party's
breach of this Agreement shall not affect this agreement to arbitrate. Moreover,
the Parties' obligations under this arbitration provision are enforceable even
after this Agreement has terminated. The invalidity or unenforceability of any
provision of this agreement to arbitrate shall not affect the validity or
enforceability of the Disputing Parties' obligation to submit their Claims to
binding arbitration or the other provisions of this agreement to arbitrate.

         SECTION 22.12 MINOR DISPUTE RESOLUTION.

         (a)      In the event there is a Claim between the Parties involving an
aggregate amount of one million dollars (US$1,000,000) or less (a "MINOR CLAIM")
that has not been resolved by mutual agreement of the Parties pursuant to
Section 22.1, then the Minor Claim shall be resolved by binding arbitration in
accordance with this Section 22.12.

         (b)      The arbitration shall be conducted under the Rules of
Arbitration of the Arbitration Center of Mexico ("CAM") as in force at the time
such arbitration is commenced (the "CAM ARBITRATION RULES").

         (c)      The arbitration proceeding shall be conducted in Mexico City,
Mexico, or any other place mutually agreed to by the Parties, and the
arbitration proceedings shall be conducted in the English language.

         (d)      The award rendered by the arbitrators shall be in writing, in
the English language, and shall set forth in reasonable detail the facts of the
Minor Claim and the reasons for the arbitrators' decision, and shall apportion
the costs of the arbitration.

         (e)      Each Disputing Party against which the arbitrators' award
assesses a monetary obligation shall pay that obligation on or before the 30th
day following the award or such other date as the award may provide, which award
shall be payable in cash in U.S. dollars unless the award specifies a different
currency.

         (f)      The arbitrators' award shall, as between the Disputing Parties
and those in privity with them, be final and entitled to all of the protections
and benefits of a final judgment, e.g., res judicata (claim preclusion) and
collateral estoppel (issue preclusion), as to all Minor Claims, including
compulsory counterclaims, that were or could have been presented to the
arbitrators. The arbitrators' award shall not be reviewable by or appealable to
any court or subject to further arbitration pursuant to Sections 22.1 through
22.11.

         (g)      It is the intent of the Parties that the arbitration
proceeding shall be conducted expeditiously, without initial recourse to the
courts and without interlocutory appeals of the arbitrators' decisions to the
courts. However, by agreeing to arbitration, the Parties do not intend to
deprive any court with jurisdiction of its ability to issue a preliminary
injunction, attachment or other form of provisional remedy in aid of the
arbitration and a request for such provisional remedies by a Disputing Party to
a court shall not be deemed a waiver of the agreement to

                                       27

<PAGE>

arbitrate contained in this Section 22. Any court order compelling arbitration
shall require that the arbitration proceedings take place in Mexico City, Mexico
as specified above. The Disputing Parties may apply to any court having
jurisdiction for orders requiring witnesses to obey subpoenas issued by the
arbitrators. Moreover, any and all of the arbitrators' orders and decisions may
be enforced if necessary by any court having jurisdiction. The arbitrators'
award may be confirmed in, and judgment upon the award entered by, any court
having jurisdiction.

         (h)      Except as may be required by applicable law or court order,
the Disputing Parties shall maintain confidentiality as to all aspects of the
arbitration, including its existence and results, except that nothing herein
shall prevent any Disputing Party from disclosing information regarding the
arbitration for purposes of enforcing the award or in any court proceeding
involving the Disputing Parties. The Parties further agree to obtain the
arbitrators' agreement to preserve the confidentiality of the arbitration.
However, a violation of this covenant shall not affect the enforceability of
this agreement to arbitrate or of the arbitrators' award.

         (i)      A Disputing Party's breach of this Agreement shall not affect
this agreement to arbitrate. Moreover, the Parties' obligations under this
arbitration provision are enforceable even after this Agreement has terminated.
The invalidity or unenforceability of any provision of this agreement to
arbitrate shall not affect the validity or enforceability of the Disputing
Parties' obligation to submit their Claims to binding arbitration or the other
provisions of this agreement to arbitrate.

         23.      JOINT OBLIGATION.

         By execution of this Master Lease, Grupo Iusacell hereby agrees to be
jointly and severally liable for all of the obligations of Lessee under this
Master Lease. In terms of Article 1987, 1988 and other related articles of the
Federal Civil Code of Mexico and related articles of other civil codes of
Mexico.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                       28

<PAGE>

         IN WITNESS WHEREOF, the parties have executed this Master Lease as of
the date first above written.

         IUSACELL ARRENDADORA, S.A. DE C.V.

                                   By:   /s/ Peter H. Burrowes
                                      -----------------------------
                                   Name:  Peter H. Burrowes
                                   Title: Attorney-in-Fact

         GRUPO IUSACELL CELULAR, S.A. DE C.V.,
         AS JOINT OBLIGOR

                                   By:   /s/ Peter H. Burrowes
                                      -----------------------------
                                   Name:  Peter H. Burrowes
                                   Title: President and General Director

                          [Master Lease Signature Page]

                                       S-1

<PAGE>

                                  MATC CELULAR, S. DE R.L. DE C.V.

                                  By:  /s/ Michael Gearon
                                      --------------------
                                  Name:  Michael Gearon
                                  Title: Attorney-in-Fact

                          [Master Lease Signature Page]

                                       S-2

<PAGE>

                                    EXHIBIT A

                                  DEFINED TERMS

         "ADDITIONAL RENT" has the meaning ascribed to such term in Section 5(c)
of this Agreement.

         "AFFILIATES" will mean, with respect to the party, person or entity in
question, any entity or person that owns or controls, is owned or controlled by
or is under common control with such party, person or entity. For the purposes
of this definition, control of any party, person or entity means ownership,
directly or indirectly, of (a) 50% or more of the voting stock, if a
corporation, and ownership of 50% or more of the equity or beneficial interest
in any other party, person or entity, or (b) 45% or more of the voting stock or
the equity or beneficial interest in such party, person or entity and management
control of such party, person or entity. The general partner of any partnership
will be deemed to control such partnership. Notwithstanding anything to the
contrary contained in this Agreement, neither (i) Verizon Communications and its
Affiliates (other than Grupo Iusacell, S.A. de C.V. (f/k/a Nuevo Grupo Iusacell,
S.A. de C.V.) and the entities included in its consolidated financial
statements), (ii) Carlos Peralta Quintero and his corporate Affiliates (other
than Grupo Iusacell, S.A. de C.V. (f/k/a Nuevo Grupo Iusacell, S.A. de C.V.) and
the entities included in its consolidated financial statements) shall be
considered Affiliates of Lessee, nor (iii) Vodafone Group PLC and its Affiliates
(other than Grupo Iusacell, S.A. de CV. (f/k/a Nuevo Grupo Iusacell, S.A. de
C.V.) and the entities included in its consolidated financial statements.

         "AGREEMENT" means this Master Lease Agreement together with its
exhibits.

         "AVAILABLE SPACE" has the meaning ascribed to such term in Section 7(c)
of this Agreement.

         "BASE RENT" has the meaning ascribed to such term in Section 5(b) of
this Agreement.

         "BUSINESS DAY" means any day other than a Saturday, Sunday or holiday
of the federal government of the United States of America or the United Mexican
States.

         "CAM" shall have the meaning ascribed to such term in Section 22.12(b).

         "CAM ARBITRATION RULES" shall have the meaning ascribed to such term in
Section 22.12(b).

         "CLAIMS" shall have the meaning ascribed to such term in Section 22.1.

         "CLOSING" means the consummation of the transfer of the Sites and other
transactions contemplated by the Purchase Agreement, which shall occur in
multiple closings (individually, a "CLOSING," and collectively, the "CLOSINGS").

         "CLOSING DATE" means the date of the applicable Closing.

                                       A-1

<PAGE>

         "COMMENCEMENT DATE" means the date on which a Site is conveyed to MATC
Celular pursuant to the Purchase Agreement.

         "DISPUTING PARTY" shall have the meaning ascribed to such term in
Section 22.1.

         "EFFECTIVE DATE" has the meaning ascribed to such term in Section 4(a)
of this Agreement.

         "FINANCING SECURED PARTIES" has the meaning ascribed to such term in
Section 13(c) of this Agreement.

         "FIRST RENEWAL TERM" has the meaning ascribed to such term in Section
4(b) of this Agreement.

         "FORCE MAJEURE" means those events constituting excuse from timely
performance by MATC Celular or Lessee of any of their respective duties and/or
obligations required under this Agreement, as described in Section 15(b).

         "GOVERNMENTAL AUTHORITY" means any federal, state, county or municipal
governmental authority, including all executive, legislative, judicial and
administrative bodies thereof.

         "GOVERNMENTAL REQUIREMENTS" means all federal, state, county or
municipal laws, ordinances, and regulations and all orders and decrees of all
Governmental Authorities.

         "HAZARDOUS MATERIAL" has the meaning ascribed to such term in Section
19 of this Agreement.

         "ICC" means the Court of Arbitration of the International Chamber of
Commerce.

         "ICC RULES" means the Rules of Arbitration of the International Chamber
of Commerce.

         "INDEMNIFYING PARTY" has the meaning ascribed to such term in Section
18(a) of this Agreement.

         "INITIAL TERM" has the meaning ascribed to such term in Section 4(b) of
this Agreement.

         "LABOR OBLIGATIONS" has the meaning ascribed to such term in Section
14(b) of this Agreement.

         "LESSEE" has the meaning ascribed to such term in the preamble of this
Agreement.

         "LESSEE'S IMPROVEMENTS AND EQUIPMENT" has the meaning ascribed to such
term in Section III(c) of the Recitals to this Agreement.

         "LESSEE MORTGAGES" has the meaning ascribed to such term in Section
13(c) of this Agreement.

         "LOSSES" has the meaning ascribed to such term in Section 14(b) of this
Agreement.

                                       A-2

<PAGE>

         "MANAGEMENT AGREEMENT" has the meaning ascribed to such term in Section
III(a) of the Recitals to this Agreement.

         "MASTER LEASE" has the meaning ascribed to such term in the preamble of
this Agreement.

         "MATC CELULAR" has the meaning ascribed to such term in the preamble of
this Agreement.

         "MAXIMUM EQUIPMENT" has the meaning ascribed to such term in Section
7(a) of this Agreement.

         "MEXICO" has the meaning ascribed to such term in Section 16(e) of this
Agreement.

         "MINOR CLAIM" shall have the meaning ascribed to such term in Section
22.12.

         "NEW EQUIPMENT" has the meaning ascribed to such term in Section 7(c)
of this Agreement.

         "NOTICE OF DISPUTE" has the meaning ascribed to such term in Section
22(a) of this Agreement.

         "OTHER TENANT" has the meaning ascribed to such term in Section 6(a) of
this Agreement.

         "PER CAPITA SHARE" has the meaning ascribed to such term in Section
5(c) of this Agreement.

         "PERMITS" means any and all certificates, licenses, permits,
authorizations, consents, special use permits, environmental studies, and other
analyses and approvals required or issued by the applicable governmental
authorities having jurisdiction in such matters required to be obtained, issued,
granted or received for the construction and use of any New Equipment.

         "PREMISES" shall have the meaning ascribed to such term in Section
III(c) of the Recitals to this Agreement.

         "PRIME LEASE" has the meaning ascribed to such term in Section 1(g) of
this Agreement.

         "PURCHASE AGREEMENT" has the meaning ascribed to such term in Section
III(b) of the Recitals to this Agreement.

         "REGION" has the meaning ascribed to such term in Section 13(a) of this
Agreement.

         "RENEWAL TERM" has the meaning ascribed to such term in Section 4(b) of
this Agreement.

         "SECOND RENEWAL TERM" has the meaning ascribed to such term in Section
4(b) of this Agreement.

                                       A-3

<PAGE>

         "SITES" means (i) those Sites, as defined in the Purchase Agreement,
purchased by MATC Celular from Lessee pursuant to the Purchase Agreement at the
initial Closing; and (ii) any Site, as defined in the Purchase Agreement,
purchased by MATC Celular from Lessee at a subsequent Closing and added to this
Master Lease pursuant to the execution of a Site Lease with respect thereto, all
of which such Sites are set forth in Schedule 1, as amended from time to time,
pursuant to Section 1(b) of this Master Lease.

         "SITE LEASE" means a Site Lease between Lessee and MATC Celular
relating to Lessee's use of the Premises at a Site, in the form attached as
Exhibit B hereto.

         "TERM" means the Initial Term and any Renewal Terms entered into
pursuant to Section 4(b) of this Agreement.

         "TERMINATION PERIOD" shall have the meaning ascribed to such term in
Section 14(c).

         "TOWER" means a radio tower structure.

         "TOWER SITE PERMITS " means any and all certificates, licenses,
building, special use and other permits, authorizations, consents, and other
approvals issued by the applicable Governmental Authority having jurisdiction in
such matters required to be obtained, issued, granted, received and/or
maintained in connection with any Sites under this Agreement, including, without
limitation, construction permits and permits issued by the applicable aviation
authorities.

                                       A-4

<PAGE>

              [NOTE: TO BE REPLACED WITH FORM FROM MEXICAN COUNSEL]

                                    EXHIBIT B
                               FORM OF SITE LEASE

[This is intended by the parties hereto to be a sample, which shall be modified
        by the mutual agreement of the parties hereto, from time to time]

                                                       [Date]

IUSACELL ARRENDADORA, S.A. de C.V.

Attention: _______________

         This Site Lease is issued by MATC, S. de R.L. de C.V. ("MATC CELULAR")
under terms of that certain Master Lease Agreement (the "MASTER LEASE
AGREEMENT") dated _______, 2000, entered into by and between MATC Celular and
IUSACELL ARRENDADORA, S.A. de C.V. for and on behalf of itself and its
affiliates ("LESSEE").

         Terms not otherwise defined herein shall have the meaning assigned to
them in the Master Lease Agreement, of even date, or the Management Agreement
dated December 29, 1999 entered into by and between MATC Celular and Grupo
Iusacell Celular, S.A. de C.V..

         [IF APPLICABLE: A COPY OF THE PRIME LEASE RELATING TO THE SITE COVERED
BY THIS SITE LEASE IS ATTACHED TO THIS EXHIBIT B AS ATTACHMENT A.]

TOWER INFORMATION:

   Tower Name:           ______________            Coordinates:  ______
   Tower Number:         ______________
   City, State and Region:________________________________________________
   This Site is (check one): ______ MATC Existing Site ______ Build-to-Suit Site

RENT AND TERM:

                  Commencement Date:      ____________________

                  Rent:    $  ________________________,  payable monthly the
                  fifth day of each month, except for the first Rent payment
                  which will be payable within twenty (20) Business Days
                  following the Commencement Date.

                  Refer to Section 4 of the Master Lease for the duration of the
                  Term (including renewal periods) and Section 5(b) of the
                  Master Lease for the annual escalation of the Rent.

                                       B-1

<PAGE>

LOCATION/IDENTIFICATION OF PREMISES

                  Height of Center of Radiation (center point of 20 foot expanse
                  comprising the "PREMISES"):_______________________

LESSEE'S IMPROVEMENTS AND EQUIPMENT INFORMATION:

         Call Sign:______________                    RX Frequency: __________
         Antenna Height:______________               Antenna Type:____________
         TX Frequency:______________                 Trans. Line: ___________

         THE SPACE TO BE LEASED FOR THE LOCATION OF LESSEE'S EQUIPMENT SHELTER
         IS DESCRIBED ON ATTACHMENT B ATTACHED TO THIS EXHIBIT B.

         LESSEE'S IMPROVEMENTS AND EQUIPMENT TO BE INSTALLED ON TOWER:

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------
                                      #1                #2                 #3                  #4
-----------------------------------------------------------------------------------------------------------
<S>                                   <C>               <C>                <C>                 <C>
QUANTITY:
-----------------------------------------------------------------------------------------------------------
MANUFACTURER:
-----------------------------------------------------------------------------------------------------------
TYPE & MODEL #:
-----------------------------------------------------------------------------------------------------------
ANTENNA WEIGHT/LENGTH:
-----------------------------------------------------------------------------------------------------------
LINE TYPE:
-----------------------------------------------------------------------------------------------------------
LINE QUALITY & DIAMETER:
-----------------------------------------------------------------------------------------------------------
ANTENNA MOUNT HEIGHT
-----------------------------------------------------------------------------------------------------------
TOWER LEG:
-----------------------------------------------------------------------------------------------------------
DIRECTION OF RADIATION:
-----------------------------------------------------------------------------------------------------------
REQUESTED MOUNTING POSITION:
-----------------------------------------------------------------------------------------------------------
</TABLE>

 TRANSMISSION AND OTHER EQUIPMENT TO BE LOCATED IN LESSEE'S EQUIPMENT BUILDING:

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------
                                      #1                #2                 #3                  #4
-----------------------------------------------------------------------------------------------------------
<S>                                   <C>               <C>                <C>                 <C>
NUMBER OF CABINETS:
-----------------------------------------------------------------------------------------------------------
# OF TRANSMITTERS PER CABINET:
-----------------------------------------------------------------------------------------------------------
MANUFACTURER:
-----------------------------------------------------------------------------------------------------------
TYPE & MODEL #:
-----------------------------------------------------------------------------------------------------------
TYPE OF SERVICE:
-----------------------------------------------------------------------------------------------------------
RACK DIMENSIONS:
-----------------------------------------------------------------------------------------------------------
RATED POWER:
-----------------------------------------------------------------------------------------------------------
CALL SIGN:
-----------------------------------------------------------------------------------------------------------
TX FREQUENCY:
-----------------------------------------------------------------------------------------------------------
RX FREQUENCY:
-----------------------------------------------------------------------------------------------------------
ELEC. SERVICE AMPS/VOLTS:
-----------------------------------------------------------------------------------------------------------
NUMBER OF OUTLETS:
-----------------------------------------------------------------------------------------------------------
POWER OUTLETS:
-----------------------------------------------------------------------------------------------------------
ERP:
-----------------------------------------------------------------------------------------------------------
DIMENSIONS (W" X D" X H")
-----------------------------------------------------------------------------------------------------------
COMBINER/# OF PORTS:
-----------------------------------------------------------------------------------------------------------
CABINET ALSO CONTAINS:
-----------------------------------------------------------------------------------------------------------
GROUND SPACE DIMENSION (IF APPL):
-----------------------------------------------------------------------------------------------------------
</TABLE>

                                       B-2

<PAGE>

         [INFORMATION SIMILAR TO THAT PROVIDED ABOVE SHALL BE PROVIDED FOR ALL
         MICROWAVE AND PAGING EQUIPMENT INSTALLED ON THE SITE, AS APPLICABLE]

SITE DRAWINGS/STRUCTURALS (IF ANY) ARE ATTACHED TO THIS EXHIBIT B AS ATTACHMENT
C.]

[DISCLOSURE OF ENVIRONMENTAL CONDITIONS REQUIRED PURSUANT TO SECTION 19 OF THE
MASTER LEASE:

________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

         Upon signature of this Site Lease, the Lessee agrees to be bound by the
provisions of the Master Lease. Any of the parties may cause this Site Lease and
the Master Lease to be registered at the Public Registry of Property of the
location of the Premises, as specified above.

IUSACELL ARRENDADORA, S.A. de C.V.         MATC Celular, S. de R.L. de C.V.

_____________________________              ____________________________
By:                                        By:
Position:                                  Position:
Date:                                      Date:

                                       B-3

<PAGE>

                                    EXHIBIT C

                               SPANISH TRANSLATION

                                       C-1

<PAGE>

                                    EXHIBIT D

         ACCESS PROCEDURES

[This is intended by the parties hereto to be a sample, which shall be modified
        by the mutual agreement of the parties hereto, from time to time]

1.       So long as the work to be performed at the Site is ground-based only,
Lessee shall have the right to enter the Site at anytime during the Term,
without notice to MATC Celular, in accordance with Section 7(f).

2.       Except for emergency situations, in the event that Lessee or any of its
employees, representatives, agents, contractors, or subcontractors enters the
Site to perform any form of maintenance, repair, installation, or inspection of
any equipment located on the tower structure, Lessee must contact MATC Celular
no less than seven (7) days prior to such visit as follows:

         a.       Call and personally speak with the Director of Operations at
                  55-5-240-2000

         b.       Fax a notification of the type of work to be performed, date
                  and time of intended visit to the Director of Operations at
                  fax number 55-5-240-2026.

3.       In the event of an emergency situation in which Lessee or any of its
employees, representatives, agents, contractors, or subcontractors needs to
enter the Site to perform emergency repairs, to the extent possible, Lessee
shall attempt to contact the Director of Operations at 55-5-240-2000 by
telephone or shall leave a message for the Director of Operations prior to their
entrance to the site and may enter such site if they have not had any contact
with the Director of Operations within two hours after leaving such message. In
the event that such contact or message is not possible, Lessee shall personally
speak with the Director of Operations as soon as practicable after the emergency
repairs have been made (but in no event more than twenty-four hours).

                                       D-1

<PAGE>

                                    EXHIBIT E

                               MICROWAVE FORMULAE

Solids: 0.75 X height on tower (ft) X diameter of the dish (ft) = Monthly Fee

Grids: 0.50 X height on tower (ft) X diameter of the dish (ft) = Monthly Fee

All such amounts will remain subject to the three percent (3%) annual increase
contained in Section 5(b) of this Master Lease

                                       D-1

<PAGE>
                              EXHIBIT J

                            Standard Sites

                                        -1-
<PAGE>

SCHEDULE 1

                                  LIST OF SITES<PAGE>
                                                                     EXHIBIT 4.4

                                                                  EXECUTION COPY

                                 ENGLISH VERSION

                    AMENDED & RESTATED MASTER LEASE AGREEMENT

         This Amended and Restated Master Lease Agreement (this "MASTER LEASE"
or "AGREEMENT") is entered into this 16th day of May, 2002, between MATC
Celular, S. de R.L. de C.V. ("MATC CELULAR"), and GRUPO IUSACELL CELULAR, S.A.
DE C.V. (f/k/a Grupo Iusacell, S.A. de C.V.), for and on behalf of itself and
its Affiliates ("LESSEE") and shall govern the relationship between the parties
as of December 1, 2001.

         Capitalized terms not otherwise defined herein shall have the meaning
assigned to them in Exhibit "A" of that certain Amended and Restated
Build-to-Suit Agreement (the "BUILD-TO-SUIT AGREEMENT"), of even date, entered
into by and between MATC Celular and Lessee and a copy of which is attached to
this Master Lease as Exhibit "A".

                                    RECITALS

         I.       RECITALS OF LESSEE. Lessee recites that:

         a)       It is a corporation duly incorporated and validly existing
under the laws of Mexico, with the power and authority to enter into this Master
Lease and to comply with its covenants and obligations as set forth hereunder,
as evidenced by Public Deed No. 33,275granted on October 6, 1992, before Public
Notary No. 1 of the Federal District, Lic. Roberto Nunez y Bandera, which first
copy is duly registered at the Public Registry of Commerce of the Federal
District, Mexico, under Commercial No. 168528,on November 27, 1992.

         b)       Its representatives are duly authorized and have the required
legal capacity to enter into this Master Lease on its behalf, and that their
authority has not been modified, restricted, revoked or otherwise amended since
the date on which it was granted, as evidenced by Public Deed No. 3,849 granted
on June 26, 2001, before Public Notary No. 212 of the Federal District, Lic.
Francisco Hugues Velez, which first copy is duly registered at the Public
Registry of Commerce of the Federal District, Mexico, under Commercial No.
168528, on July 4, 2001.

         c)       The terms and conditions of this Master Lease do not
contravene any of its obligations under any agreements, permits, concessions
and/or authorizations to which it is a party and therefore does not constitute a
breach of any of such agreements, permits, concessions and/or authorizations.

<PAGE>

         II.      RECITALS OF MATC CELULAR. MATC Celular recites that:

         a)       It is a corporation duly incorporated and validly existing
under the laws of Mexico, with the power and authority to enter into this Master
Lease and to comply with its covenants and obligations as set forth hereunder,
as evidenced by Public Deed No. 43,972 granted on October 5, 1999, before Public
Notary No. 1 of the Federal District, Roberto Nunez y Bandera, which first copy
is in the process of being duly registered at the Public Registry of Commerce of
Mexico City, Mexico.

         b)       Its representatives are duly authorized and have the full
legal capacity to execute this Master Lease on its behalf, and that their
authority has not been modified, restricted, revoked or otherwise amended since
the date on which it was granted, as evidenced by Public Deed No. 43,972 granted
on October 5, 1999, before Public Notary No. 1 of the Federal District, Roberto
Nunez y Bandera, which first copy is pending to be duly registered at the Public
Registry of Commerce of Mexico City, Mexico.

         c)       The terms and conditions of this Master Lease do not
contravene any of its obligations under any agreements, permits, concessions
and/or authorizations to which it is a party and therefore does not constitute a
breach of any of such agreements, permits, concessions and/or authorizations.

         III.     RECITALS OF THE PARTIES. The parties recite that:

         a)       MATC Celular and Lessee have previously entered into a Master
Lease Agreement, dated as of December 29, 1999 (the "ORIGINAL MASTER LEASE
AGREEMENT"), relating to the lease of space by Lessee at certain MATC Sites.

         b)       Contemporaneously with the execution and delivery of this
Master Lease, MATC Celular and Lessee have entered into the Build-to-Suit
Agreement, pursuant to which MATC Celular and Lessee have amended and restated
the terms of that certain Build-to-Suit Agreement dated as of December 29, 1999
(the "ORIGINAL BUILD-TO-SUIT AGREEMENT"), and further pursuant to which Lessee
and certain of its Affiliates have engaged MATC Celular to construct and develop
at least eighty percent (80%) of Lessee's requirements for Towers in the Mexico
Market upon which Lessee shall lease space; and

         c)       The parties desire to amend and restate the Original Master
Lease Agreement as provided herein.

         d)       Lessee wishes to lease from MATC Celular: (i) at all MATC
Sites, space within equipment shelters constructed and owned by MATC Celular in
accordance with the Build-to-Suit Agreement and the repair and maintenance
thereof, the provision of which by MATC Celular shall include air conditioning,
general lighting, connections for utility services, and a grounding system for
Lessee's electronics; (ii) at all MATC Sites, a generator shelter and associated
ground space for

                                       -2-

<PAGE>

the installation by Lessee of Lessee's generator, if any; (iii) with respect to
all MATC Sites, non-exclusive use of space on the applicable tower within a
twenty (20) foot expanse comprised of the ten (10) feet above and ten (10) feet
below the height of the center of radiation of Client's Improvements and
Equipment located on the applicable tower structure (unless such space is
otherwise defined in the applicable Site Lease), and (iv) non-exclusive use of
certain rights of way granted under Section 1(f) of this Agreement
(collectively, the "PREMISES"), all at locations more particularly described in
a supplement to be executed in the form attached to this Master Lease as Exhibit
B-1 (with respect to Build-to-Suit Sites) and Exhibit B-2 (with respect to MATC
Existing Sites), which forms may be mutually amended by the parties hereto from
time to time, (the "SITE LEASE"), each of which Site Leases shall be governed by
the terms of this Master Lease and which shall become a part of this Master
Lease as if fully set forth herein. Client's Improvements and Equipment at MATC
Sites in accordance with the Build-to-Suit Agreement shall hereinafter be
referred to as "LESSEE'S IMPROVEMENTS AND EQUIPMENT."

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which the parties acknowledge, the parties agree as follows:

         1.       LEASE OF PREMISES.

         (a)      MATC Celular does or will lease or own, construct and operate
MATC Sites under the terms of the Build-to-Suit Agreement. Lessee shall lease
from MATC Celular the Premises within each of the Build-to-Suit Sites to be
built by MATC Celular and each MATC Existing Site leased by Lessee under the
terms of the Build-to-Suit Agreement, in consideration for which Lessee shall
pay rent as specified in Section 5 of this Agreement and the applicable Site
Lease, under the terms and conditions of this Master Lease. Upon identification
of an MATC Site pursuant to the Build-to-Suit Agreement and identification of
the Premises corresponding to each MATC Site, as provided below, each Premises
shall become subject to this Master Lease and a corresponding Site Lease, for
the purposes hereof, pursuant to article 1826 of the Mexican Civil Code for the
Federal District and the applicable provisions of the Civil Codes of the
jurisdictions in which any MATC Site is located.

         (b)      Within seven (7) Business Days after the selection by Lessee
of an MATC Site pursuant to the terms of the Build-to-Suit Agreement, MATC
Celular will provide a notice to Lessee identifying the Premises to be leased to
Lessee in the corresponding Site Lease, which notice shall include the location
and specifications for the Premises, as well as the Base Rent and Additional
Rent (as such terms are defined in Section 5 below) corresponding to such
Premises, and will deliver to Lessee a copy of the corresponding Site Lease duly
executed by MATC Celular. The effective date (the "COMMENCEMENT DATE") of each
Site Lease will be the Completion Date of an MATC Site, as provided under the
Build-to-Suit Agreement.

         (c)      Lessee shall execute and deliver to MATC Celular a copy of
each Site Lease no later than three (3) Business Days following its receipt. The
parties agree that the execution and delivery

                                       -3-

<PAGE>

by Lessee of any Site Lease shall not be a condition to the effectiveness of
such Site Lease in accordance with the provisions of subsection (b) of this
Section 1.

         (d)      The parties agree that either party may request the
registration of any Site Lease at the Public Registry of Property corresponding
to the jurisdiction where any MATC Site is located, as specified in the
corresponding Site Lease, and all costs and expenses associated with such
registration shall be borne solely by the requesting party.

         (e)      As of the Commencement Date, MATC Celular will grant the
Lessee the use of the Premises as provided in the Specifications of the
Build-to-Suit Agreement, which Premises shall be ready to be used by Lessee,
under terms of Article 2412 of the Civil Code for the Federal District, and
shall comply with all of its obligations thereunder or under the applicable
provisions of the Civil Codes of the jurisdiction in which any Premises are
located.

         (f)      MATC Celular shall lease to Lessee and Lessee shall lease from
MATC Celular the Premises identified in each Site Lease, as of the Commencement
Date and under terms of this Master Lease. Subject to Section 7(d), MATC Celular
grants Lessee the right to install and maintain Lessee's Improvements and
Equipment on the Premises and rights to install and maintain utility wires,
cables, conduits and pipes on the MATC Site including over, under or along a
right of way extending from a public right of way to the MATC Site, and to
utilize a right of way for access to the MATC Site as described in Section 7(f)
hereof and in the applicable Site Lease.

         (g)      If the Premises are a part of property leased by MATC Celular
under any agreement with the owner of the property (the "PRIME LEASE"), a copy
of the Prime Lease will be delivered to Lessee prior to the delivery of the
corresponding Site Lease (redacted as deemed reasonably necessary by MATC
Celular). It will be the sole responsibility of Lessee to read and familiarize
itself with the terms of the Prime Lease. Notwithstanding anything to the
contrary contained in this Master Lease, all terms, covenants and conditions
contained in this Master Lease shall be specifically subject and subordinate to
the terms and conditions of any applicable Prime Lease. In the event that any of
the provisions of the Prime Lease supercede or contradict the terms of this
Master Lease (other than Sections 3, 5, 6, 9, and 13 hereof), such terms of this
Master Lease shall be deemed deleted and superceded to the extent of the
contradiction as applicable to the space used by Lessee. In the event the Prime
Lease expires or is terminated prior to the expiration of the Initial Term or
any Renewal Term (as such terms are defined in subsection (b) of Section 4), the
corresponding Site Lease shall terminate as between MATC Celular and Lessee on
the effective date of termination of the Prime Lease, and MATC Celular shall
have no liability to Lessee therefor. MATC Celular shall give Lessee written
notice of any such termination promptly following its receipt of notice from the
lessor under the Prime Lease. A copy of the applicable Prime Lease shall be
attached to the relevant Site Lease as Attachment A, redacted as deemed
reasonably appropriate by MATC Celular.

         (h)      The parties hereto agree that the terms and conditions herein
shall be and are binding upon and exclusive to each party hereto and their
respective Affiliates to the extent such

                                       -4-

<PAGE>

Affiliates become parties to this Agreement with respect to any lease of space
by Lessee or any of its Affiliates entered into during the Term of this
Agreement with respect to any MATC Site or then-owned or operated by MATC
Celular or any of its Affiliates. The parties hereto acknowledge and agree that
prior to the execution of any Site Lease for an MATC Existing Site or the
commencement of any Services under the BTS Agreement for any Build-to-Suit Site
with respect to any of Client's Affiliates, such Affiliate(s) shall execute a
joinder to this Agreement in the form attached hereto as Exhibit E and upon such
execution, the terms and conditions of this Agreement shall directly bind such
Affiliate and shall not be deemed as any form of assignment or sublease of this
Agreement pursuant to Section 13. Lessee represents and warrants that as of the
date hereof, no Site Leases were executed by any Lessee Affiliate that did not
also execute a Joinder in accordance with Section 1(h). This Agreement shall not
be applicable to any communication tower, building or shelter (a) which is
managed or marketed by MATC Celular, as agent or representative, on behalf of a
third party unless MATC Celular specifically agrees otherwise, (b) which is not
constructed or developed by Lessee pursuant to the Build-to-Suit Agreement, or
(c) which is owned by any party other than MATC Celular or its Affiliates. The
parties acknowledge that each Site Lease shall be signed by MATC Celular and
Lessee or one of its respective Affiliates and shall directly bind such
Affiliate and not be deemed as any form of assignment or sublease of this
Agreement pursuant to Section 13. Lessee warrants and represents that it has the
authority to execute and deliver this Agreement and to cause its Affiliates to
execute and deliver a joinder to this Agreement and that, effective upon such
execution, each such Affiliate makes the representations set forth in the
Agreement and that it shall be deemed to be Lessee for all purposes under this
Agreement, and is bound by all terms, covenants and conditions contained in this
Agreement, as Lessee, as if such Affiliates were an original party to this
Agreement.

         2.       USE OF THE PREMISES.

         Subject to Section 3, the Premises may be used by Lessee only to
install, maintain, repair, replace, remove and operate Lessee's Improvements and
Equipment on or in the Premises for the purposes of a telecommunications
facility and uses incidental thereto in connection with the provision of
wireless telecommunications services including, without limitation, cellular,
PCS, wireless local loop, paging, and fiber optic and microwave transmission
services. MATC Celular agrees to cooperate with Lessee, at Lessee's expense, in
making application for and obtaining all Client Permits.

         3.       CONSTRUCTION AND ALTERATIONS.

         (a)      Unless expressly provided otherwise in the Build to Suit
Agreement, Lessee shall be solely responsible for all costs and expenses
associated with the purchase, installation, repair, maintenance and alteration
of Lessee's Improvements and Equipment.

         (b)      None of Lessee's Improvements and Equipment shall be installed
on the Premises nor shall any construction or alteration pertaining to Lessee's
Improvements and Equipment

                                       -5-

<PAGE>

commence until Lessee has submitted its construction and installation plans and
list of contractors and subcontractors to MATC Celular in writing, and such
plans and list have been approved in writing by MATC Celular. MATC Celular's
approval of Lessee's contractor and subcontractor list shall not be unreasonably
withheld, conditioned or delayed; provided, however, that MATC Celular shall
reserve the right, from time to time, to notify Lessee in writing of MATC
Celular's reasonable desire to remove such contractor or subcontractor from the
approved list. MATC Celular's approval of Lessee's initial installation and
associated plans and approvals shall not be unreasonably withheld, conditioned
or delayed. Lessee shall not alter any plans so approved without following the
same procedures. Lessee shall be responsible for ensuring that all external and
internal wiring and cabling installed by Lessee in the Premises is properly
grounded to the grounding ring; provided, however, that MATC Celular shall be
responsible for providing a common grounding ring. Lessee shall obtain MATC
Celular's prior written approval of such grounding plans, which approval shall
not be unreasonably withheld, conditioned or delayed.

         4.       TERM OF SITE LEASES AND MASTER LEASE; EXTENSION PERIODS.

         (a)      The term of this Agreement shall commence on the date first
written above (the "EFFECTIVE DATE") and, unless earlier terminated in
accordance with Section 10, shall remain in effect with respect to each
individual fully executed Site Lease for so long thereafter as such Site Lease
remains in effect pursuant to Sections 4(b) and (c).

         (b)      The initial term of each Site Lease shall commence on the
Commencement Date for such Site Lease and shall continue for ten (10) years (the
"INITIAL TERM"). The term of each Site Lease may be extended as follows: (i) the
term shall be extended automatically beyond its Initial Term for five (5) years
(the "FIRST RENEWAL PERIOD") unless Lessee notifies MATC Celular that it does
not wish to extend the term and such notice is given at least 90 days before the
First Renewal Term is scheduled to begin, and (ii) the term shall be further
extended beyond the First Renewal Term for five (5) years (the "SECOND RENEWAL
TERM"; each of the First and Second Renewal Terms are sometimes referred to
herein as a "RENEWAL TERM") unless Lessee notifies MATC Celular that it does not
wish to extend the term and such notice is given at least 90 days before the
Second Renewal Term is scheduled to begin. The lease term of any Site Lease
shall be the period commencing on the first day of the Initial Term and ending
on the last day of the last applicable Renewal Term, if so renewed, subject to
the provisions of Section 1(g) herein.

         (c)      Notwithstanding the provisions of this Section 4, any Site
Lease hereunder may be terminated, without any further obligation by either
party to the other, by Lessee, prior to December 29, 2009 ("TERMINATION
PERIOD"), in the event that a man-made obstruction constructed subsequent to
Lessee's installation (or later modification) adversely affects Lessee's RF
requirements with respect to the operation of such affected equipment; provided,
however, that in no event may Lessee terminate more than an aggregate of five
percent (5%) of all of the Site Leases executed by Lessee hereunder during the
Termination Period pursuant to this Section 4(c).

                                       -6-

<PAGE>

         5.       RENT; REIMBURSABLE COSTS.

         (a)      The rent payable to MATC Celular by Lessee for the Premises
under each Site Lease shall be equal to the Base Rent (as defined in
subparagraph (b) below) in effect on the Commencement Date of the applicable
Site Lease and shall be payable thereafter, in advance, in accordance with
subparagraph (b) and (d) below and the Additional Rent (if any, as defined in
subparagraph (c) below) shall be payable, in advance, in accordance with
subparagraph (d) below, both without demand.

         (b)      The base rent for each MATC Site under this Master Lease
initially shall be the amount of Two Thousand Ninety Dollars and 90/100 U.S. Cy.
(US$2,090.90) per month (the "BASE RENT"), plus the corresponding value added
tax, if any. The parties hereto acknowledge and agree that the Base Rent payable
hereunder is premised upon the installation of the Lessee's Improvements and
Equipment as specifically described in the applicable Site Lease but in no event
to exceed the structural capacity (windload, weight, etc...) (including, without
limitation, the dimensions) of the Maximum Equipment (as such term is defined in
Section 7 herein). The Base Rent shall be increased on July 1, 2002 and each
July 1st thereafter by three percent (3%) over the Base Rent in effect for the
immediately preceding year. Lessee acknowledges that Base Rent under this Master
Lease is intended to increase annually by three percent (3%). Accordingly, the
initial Base Rent under any Site Lease entered into after the date hereof shall
be adjusted to account for a three percent (3%) increase on July 1st of each
year beginning on July 1, 2002. The annual escalator provided for in this
subsection (b) shall apply to the Base Rent under this Master Lease, the
Original Master Lease Agreement and each and every Site Lease executed under
this Master Lease or the Original Master Lease Agreement. Payment of Base Rent
and Additional Rent (if any, as defined in subsection (c) below) shall commence,
with respect to each Site Lease, on the applicable Commencement Date of the
relevant Site Lease and on the first day of each month thereafter during the
Term; provided, however, that with respect to the initial payment for the first
month of the Initial Term of each Site Lease only, such payment shall be for a
pro-rata share of the Base Rent due for the remainder of the then-current
calendar month only. Lessee acknowledges that the Base Rent payable under any
Site Lease executed prior to the date hereof pursuant to the terms of the
Original Master Lease should reflect an initial Base Rent of Two Thousand
Dollars and 00/100 U.S. Cy. (US$2,000.00) per month which was adjusted on
December 29, 2000 to reflect a three percent (3%) increase over the Base Rent
then in effect and again on July 1, 2001 to reflect a one and a half percent
(1.5%) increase over the Base Rent then in effect, regardless of the
Commencement Date of any applicable Site Lease and the amount actually invoiced
by MATC Celular.

         (c)      In addition to the Base Rent payable under this Section 5,
Lessee also shall pay to MATC Celular a monthly amount equal to its per capita
portion (based on the number of tenants who lease space on the applicable Tower
for a rent equal to or in excess of seventy-five percent (75%) of the Base Rent
then-payable by Lessee at the applicable Site ("PER CAPITA SHARE")) of MATC
Celular's ground rent (if any) and real property taxes (if any) payable with
respect to the

                                       -7-

<PAGE>

applicable MATC Site (together with the additional rent described in Section
7(c) herein, "ADDITIONAL RENT"); provided, however, that with respect to
Build-to-Suit Sites only (i) Lessee's Per Capita Share of such expenses shall be
limited to the amount of space MATC Celular is reasonably required to obtain in
order to meet the Specifications and not any excess space (whether building or
ground space) that MATC Celular elected to acquire for its own account unless
such excess was required in order to meet the Specifications, and (ii) in the
event that the rental income (excluding service and installation fees and any
pass-through expenses, including, without limitation, ground rent, taxes,
utilities, etc.) that MATC Celular is due to collect from Other Tenants at any
particular Build-to-Suit Site exceeds Six Thousand One Hundred Fifty Three and
22/100 United States Dollars (US$6,153.22) (which amount shall be increased on
each December 29 of each year, beginning on December 29, 2002, by an amount
equal to three percent (3%)) in any given calendar month, Lessee shall be
relived of any obligation to pay its Per Capita Share of the ground rent and
real property taxes at such Build-to-Suit Site during that calendar month;
provided, however, if any uncollected rental income is delinquent by ninety (90)
days or more, MATC Celular may retroactively recalculate and prospectively
calculate Lessee's entitlement to an abatement of Lessee's Per Capita Share
hereunder with respect to the affected Site(s) during any such period of
delinquency by Other Tenants by excluding such uncollected rents from the
amounts MATC is due to collect from Other Tenants. To the extent that MATC
Celular is required by the ground lease to pay the ground rent in United States
dollars, Client shall be required to pay such portion of the Additional Rent in
United States dollars. Payment of the Additional Rent set forth in this Section
5(c) shall commence on the Commencement Date of the applicable Site Lease;
provided, however, that, with respect to Build-to-Suit Sites, Lessee shall also
be obligated on the applicable Commencement Date to pay MATC Celular an amount
equal to a Per Capita Share of the ground rent and real estate taxes (if any)
that MATC Celular paid during the period from the execution of the applicable
Site Lease (or the date by which the Site Lease is required to be executed if
Lessee fails to properly execute such Site Lease) through the Commencement Date
of the applicable Site Lease. With respect to Build-to-Suit Sites, MATC Celular
shall be obligated to use commercially reasonable efforts to obtain a rent-free
and tax-free option for each such ground lease for the period prior to the
Completion of the Build-to-Suit Site. MATC Celular will notify Lessee each time
any Other Tenant (as defined Section 6(a)) installs its equipment on an
applicable MATC Site.

         (d)      All Base Rent and Additional Rent due hereunder shall be paid
by Lessee to MATC Celular monthly, in advance. The first monthly payment shall
be due twenty (20) Business Days following the Commencement Date for each Site
Lease and on the fifth day of each calendar month thereafter. The Additional
Rent and Base Rent for any fractional month at the beginning or at the end of
the Initial Term or any Renewal Term shall be prorated. The Base Rent and
Additional Rent payments shall be effected by deposit of immediately available
funds to MATC Celular at an address to be identified to Lessee, in writing,
prior to the first Commencement Date of a Site Lease hereunder, as such address
may be changed from time to time upon written notice by MATC Celular to Lessee.

                                       -8-

<PAGE>

         (e)      In the event of any late payment of the Base Rent and/or
Additional Rent due under any Site Lease, without prejudice to any other rights
or remedies available to MATC Celular under this Master Lease or any applicable
laws, (i) Lessee shall pay interest on any unpaid portion of such Base Rent and
Additional Rent, as of the date payment was due and until payment in full, at a
rate per annum of LIBOR (as determined by Citibank N.A. in New York) plus 200
basis points, calculated on the basis of a year of three hundred and sixty (360)
days and the number of actual days elapsed, (ii) in addition, in the event that
any payment due under Site Lease remains outstanding for ninety (90) days or
more following each respective due date thereunder, Lessee shall pay, as
liquidated damages (pena convencional), an amount equivalent to one (1) payment
of one-twelfth (1/12) of the Base Rent due for the applicable Site Lease on the
ninety-first (91st) day and at the end of each subsequent thirty (30) days
thereafter, and (iii) in addition, if Lessee is in default on the payment of
Base Rent and/or Additional Rent for six (6) months or more with respect to ten
percent (10%) or more of the Site Leases within any Region (as defined in
Section 13(b) herein) within any consecutive three (3) month period, then in
addition to any other remedies to which MATC Celular may be entitled under this
Section 5(e) and Section 10 hereof, Lessee shall immediately prepay the Base
Rent due hereunder for each MATC Site to MATC Celular for the remainder of the
then-current term for all of the Site Leases then in effect in such Region(s),
provided, however, that upon MATC Celular's receipt of such prepaid rent in
full, Lessee shall no longer be in default with respect to the payment of any
such Base Rent during the then-current term.

         (f)      In order to secure compliance of Lessee's payment obligations
hereunder, Lessee shall deliver to MATC Celular a performance bond issued by a
Mexican bonding institution of repute, approved by MATC Celular in writing,
within twenty (20) Business Days after the Commencement Date for each Site
Lease, for an amount equal to the aggregate amount of the monthly payments of
the Base Rent and Additional Rent due under the corresponding Site Lease for the
subsequent twelve (12) month period. Lessee shall provide MATC Celular a renewal
of such bond policies yearly, no later than twenty (20) Business Days after the
anniversary of the Commencement Date, for an amount equal to the outstanding
Base Rent and Additional Rent payable through the subsequent twelve (12) month
period, as adjusted under provisions of this Section 5. MATC Celular and Lessee
acknowledge and agree that any one Affiliate of Lessee may obtain the foregoing
bond in its name for and on behalf of and for the benefit of all or any of its
Affiliates hereunder.

         (g)      Notwithstanding anything to the contrary in this Section 5,
the parties hereto acknowledge and agree that with respect to any MATC Existing
Site upon which Lessee elects to install only the Repeater Equipment or
Microcell Equipment (as hereinafter defined) and so long as neither Lessee nor
any of its Affiliates has any other equipment installed upon the affected MATC
Existing Site ("SMALL SITE"), the Base Rent to be paid by Lessee shall be
negotiated by the parties hereto, in good faith, and on a site-by-site basis as
set forth in the applicable Site Lease; provided, however that:

                                       -9-

<PAGE>

                  (i)      In the event that MATC Celular makes or receives a
         bona fide offer pursuant to which a third party would enter into a
         sublease, license or other occupancy agreement with respect to the last
         available portion of the Small Site which could accommodate the Maximum
         Equipment (the "RIGHT OF FIRST REFUSAL SPACE") during the Term hereof
         and MATC Celular intends to accept such offer or such potential third
         party otherwise proposes to enter into such agreement, then MATC
         Celular will promptly send written notice (the "RIGHT OF FIRST REFUSAL
         NOTICE") to Lessee offering to lease the Right of First Refusal Space
         to Lessee under terms and conditions no more favorable to the proposed
         tenant than those contained in this Agreement with respect to the
         Maximum Equipment at the then-current Base Rent in accordance with
         Section 5(b) above (the "RIGHT OF FIRST REFUSAL"). Delivery of the
         Right of First Refusal Notice will constitute an offer by MATC Celular
         to sublease the Right of First Refusal Space to Lessee at the rent,
         terms and conditions described this Agreement. Lessee will have five
         (5) Business Days after Lessee's receipt of the Right of First Refusal
         Notice (which five (5) Business Day period is referred to herein as the
         "ACCEPTANCE PERIOD") to elect to exercise the Right of First Refusal.
         If Lessee elects to exercise the Right of First Refusal, Lessee will
         notify MATC Celular in writing within the Acceptance Period of Lessee's
         intent to exercise such right, whereupon the Right of First Refusal
         will become a binding contract for the lease of the Right of First
         Refusal Space with respect to the Maximum Equipment and Lessee and MATC
         Celular will execute a Site Lease attached hereto as provided in this
         Section. If Lessee does not notify MATC Celular in writing within the
         Acceptance Period of Lessee's election to exercise its Right of First
         Refusal on such terms and conditions, Lessee's right to exercise its
         Right of First Refusal on such terms and conditions will terminate; and
         MATC Celular may sublease or license the Right of First Refusal Space
         to the third party. In the event that Lessee exercises its Right of
         First Refusal hereunder, Lessee may, upon no less than thirty (30) days
         prior written notice to MATC Celular, terminate the Site Lease
         associated with the Repeater Equipment or Microcell Equipment at the
         Small Site. Notwithstanding anything to the contrary herein, Lessee
         acknowledges that its Right of First Refusal hereunder shall be subject
         and secondary to any pre-existing and conflicting right to any third
         party.

                  (ii)     At any time during the Term, Lessee may convert the
         Site Lease related to the Small Site into a Site Lease for the Maximum
         Equipment so long as (x) the Commencement Date for the Initial Term of
         the Site Lease associated with the Maximum Equipment shall be the
         earlier of the date upon which Lessee installs Lessee's Improvements
         and Equipment thereunder or sixty (60) days following the date upon
         which Lessee delivered its notice to MATC Celular of its intention to
         convert such Small Site into an MATC Site which will accommodate
         Lessee's Maximum Equipment, (y) the space within which Lessee intends
         to install the Maximum Equipment or any part thereof is not subleased,
         licensed or otherwise occupied by a third party at the time of Lessee's
         providing the notice described above, and is not then subject to a
         written option, ongoing negotiations or other commitment agreement
         between MATC Celular permitting the use or occupancy of the requested
         space by a prospective third party and (z) Lessee's

                                      -10-

<PAGE>

         proposed use would not cause interference with any existing third party
         or any prospective third party under an aforementioned option or
         commitment agreement, or impair the structural integrity of the antenna
         structure.

"REPEATER EQUIPMENT" is defined as cellular repeater equipment not to exceed one
(1) equipment cabinet, a six (6) panel antenna with a vertical height of no more
than eighteen (18) inches, and six (6) coaxial cables not to exceed 1/4 inch
each. "MICROCELL EQUIPMENT" is defined as a single sector cellular transmission
and reception equipment not to exceed one (1) equipment cabinet, two (2) panel
antennas with a vertical height of no more than thirty-two (32) inches and two
(2) coaxial cables not to exceed 1 5/8 inch each that can be stringed together
to cover more than one sector).

         (h)      Should MATC Celular fail to provide permanent or provisional
power at a Build-to-Suit Site, Lessee's obligation to pay Base Rent and
Additional Rent at such Build-to-Suit Site shall be suspended until MATC Celular
provides permanent or provisional power at the Build-to-Suit Site, provided that
Lessee has issued a Provisional Acceptance Notice identifying such failure to
provide permanent or provisional power.

         6.       RENT REDUCTIONS AND OTHER TENANTS.

         (a)      The parties hereby agree and acknowledge that premises in each
MATC Site, other than the Premises, may be rented to third parties (each an
"OTHER TENANT") by MATC Celular, under terms and subject to the conditions
established by MATC Celular consistent with MATC Celular's obligations under
Section 8 hereof. For each additional lease agreement entered into by MATC
Celular with an Other Tenant that will use premises on a Build-to-Suit Site (but
not on an MATC Existing Site) to provide wireless telecommunication services
(including, without limitation, cellular, PCS, wireless local loop, paging,
microwave and fiber transmission), the Base Rent payable under the applicable
Site Lease will be reduced, per month and per each such Other Tenant, by US$200
(two hundred Dollars 00/100 U.S. Cy.); provided that, the recurring monthly rent
paid by the Other Tenant is at least US$1,500.

         (b)      The parties agree that if the actual average per-Tower Third
Party Revenues (as defined below) of MATC Celular derived exclusively from the
rent of the Build-to-Suit Sites (and specifically excluding MATC Existing Sites)
to Other Tenants exceeds US$5,800.00 (Five Thousand Eight Hundred and 00/100
U.S. Cy.) (the "TARGET INCOME"), for any month prior to December 29, 2002,
Lessee will be exempt from payment of the corresponding Base Rent payments (but
not the Additional Rent payments) for the relevant Premises, during those
subsequent months in which the Target Income is exceeded. MATC Celular will
notify Lessee in writing in the event the Target Income is exceeded in any given
month. For purposes of this subparagraph (b) only, "THIRD PARTY REVENUES" shall
be defined as the average monthly rental payments (based on the monthly
recurring rent due during the initial term of the associated lease agreement
without taking into account increases based on inflation or similar annual
escalators or pass-through of site expenses) due to MATC Celular from Other
Tenants (but not Lessee or any of

                                      -11-

<PAGE>

its Affiliates) who utilize space on the relevant Build-to-Suit Site and
excluding any revenues derived from Other Tenants by MATC Celular that are for
reimbursements of taxes, utilities, or other reimbursable costs, administrative
or interest charges, one-time payments, or fees for specific services performed
by MATC Celular or its affiliates (for example, installation of equipment or
site acquisition work fees) and any tenants who are then in default with respect
to the payment of rent to MATC Celular.

         (c)      During the term of this Agreement, MATC Celular agrees to keep
all usual and proper records and books of account and all usual and proper
entries relating to this Agreement, and Lessee may conduct an audit of MATC
Celular's records applicable to (i) the calculation of the rent reductions under
this Section 6, (ii) the Per Capita Share under Section 5(c), and (iii) MATC
Celular's compliance with the Prime Leases and legal and regulatory requirements
at each of the Sites (provided, however, that any failure by MATC Celular to
comply will not be deemed a default under this Agreement so long as Lessee does
not suffer any materially adverse consequence as a result thereof). Any such
audit will be conducted by a designated Lessee auditor or by an independent
certified public accountant selected by Lessee, and will be conducted only with
reasonable advance written request. The audit will be conducted during regular
business hours and will be conducted in such a manner as not to interfere with
MATC Celular's normal business activities. Any fees or costs incurred by an
independent certified public accountant will be paid for by Lessee. Lessee
recognizes and agrees that information learned during an audit is confidential
and that such information may be used only in further disposition of the audit,
including, without limitation, to negotiate, prosecute, and resolve disputes.

         7.       FACILITIES; UTILITIES; ACCESS.

         (a)      Lessee, at its sole cost and expense, has the right to
install, maintain and operate on each of the Premises, Lessee's Improvements and
Equipment, which are owned by Lessee and/or any of its Affiliates, as more
specifically described in the applicable Site Lease, but in no event may
Lessee's Improvements and Equipment exceed the structural (e.g., wind load,
weight, etc.) capacity required on the Tower for twelve (12) panel Allen Telecom
ASPD-963 antennas, 12 (twelve) 1 5/8 inch coax cables, one (1) six foot diameter
Andrew solid microwave antenna and an associated 1 5/8 inch cable run, and one
(1) GPS antenna located at the same height on the antenna structure
(collectively, "MAXIMUM EQUIPMENT"). Without MATC Celular's prior written
consent, Lessee shall not have the right to relocate Lessee's Improvements and
Equipment to any location on a MATC Site. All construction and installation work
necessary or convenient for the use of Lessee's Improvements and Equipment shall
be performed in a good and workmanlike manner. Subject to Section 7(b), title to
Lessee's Improvements and Equipment shall be held by Lessee. Lessee's
Improvements and Equipment shall remain Lessee's personal property and are not
fixtures. Notwithstanding anything to the contrary in this Master Lease, in the
event that Lessee elects to install less than Maximum Equipment as of the
Commencement Date, Lessee shall reserve the right at any time during the Initial
Term or any Renewal Term thereof, to install additional improvements and
equipment (or substitute different

                                      -12-

<PAGE>

improvements and equipment) on the Premises for no additional rent up to the
Maximum Equipment, subject to the provisions of Sections 8 and 15 herein;
provided that such additional or substitute improvements and equipment will not
(i) create interference with the then-existing improvements and equipment of any
Other Tenant upon installation, and (ii) exceed the structural capacity required
on the tower for Maximum Equipment.

         (b)      Lessee shall have the right to remove Lessee's Improvements
and Equipment under any Site Lease at any time before the expiration or earlier
termination of the applicable Site Lease so long as Lessee is not then in
default, and Lessee shall be obligated to remove Lessee's Improvements and
Equipment prior to the expiration or termination of the applicable Site Lease.
Lessee shall restore the Premises to as good a condition as initially received
by Lessee, except for ordinary wear and tear, and Lessee shall be solely
responsible for all costs and expenses associated with the removal of Lessee's
Improvements and Equipment, including, without limitation, the repair of any
damage to the Premises or MATC Site caused by such removal. If Lessee fails to
remove Lessee's Improvements and Equipment prior to the expiration or earlier
termination of the Site Lease, MATC Celular may, at its option and upon no less
than thirty (30) days prior written notice to Lessee, cause any such property to
be removed and stored at the expense of Lessee. In the event that Lessee's
Improvements and Equipment are not claimed by Lessee within thirty (30) days
following notice from MATC Celular to Lessee of its removal, subject to any
existing lien, security interest or other encumbrance, Lessee shall, and hereby
promises and agrees to transfer title to such property to MATC Celular and to
execute and deliver any documents necessary to effect such transfer of title).
In such case, the parties agree that transfer of title of such property by
Lessee to MATC Celular shall be considered as liquidated damages (pena
convencional) resulting from Lessee's failure to remove Lessee's Improvements
and Equipment in accordance with the terms and conditions of this Agreement. The
parties hereby specifically acknowledge that MATC Celular will be under no
obligation to repay Lessee for any construction, improvements or work performed
on an MATC Site by Lessee, and Lessee hereby waives the provisions of articles
2423 and 2424 of the Civil Code for the Federal District and the applicable
provisions of the Civil Codes of the jurisdictions in which any MATC Site is
located. The authorization to remove all or part of Lessee's Improvements and
Equipment prior to the termination of the Master Lease and/or the respective
Site Lease shall not be interpreted as a release of Lessee's responsibility to
perform its respective obligations under such agreements.

         (c)      If Lessee desires to install additional improvements and
equipment at any MATC Site on space on the applicable structure outside of the
Premises or that will exceed the wind load on the Tower of the Maximum Equipment
("NEW EQUIPMENT"), MATC Celular and Lessee shall negotiate in good faith the
terms of a site lease providing for the installation of such New Equipment on
the applicable MATC Site; provided, however, that MATC Celular's obligation to
negotiate in good faith for the lease of additional space and/or capacity on a
MATC Site shall be conditioned upon the existence of space on such structure
which is unoccupied and not leased under, or otherwise covered by, another
agreement (or an agreement then being negotiated by MATC Celular) permitting
another third-party to use or occupy such portion of the applicable MATC Site
("AVAILABLE SPACE") and the obtaining of any necessary Permits for the
installation of

                                      -13-

<PAGE>

such New Equipment. With respect to MATC Existing Sites, the rent payable by
Lessee for the use of additional space and/or capacity for the installation of
such New Equipment shall be negotiated on a Site-by-Site basis. With respect to
Build-to-Suit Sites, the rent payable by Lessee for the use of additional space
and/or capacity for the installation of such New Equipment other than microwaves
will be based upon the additional structural capacity required for such New
Equipment, pursuant to the following formula: first, the structural capacity on
a Tower required by the Maximum Equipment will be determined based on the
assumption that the Maximum Equipment is installed at the height of Lessee's
Improvements and Equipment as provided in the applicable Site Lease; second, the
structural capacity required for the New Equipment will be determined based upon
the applicable tower manufacturer's specifications and the proposed height of
such New Equipment; and third, the additional rent will be determined based upon
the structural capacity required for such New Equipment in proportion to the
structural capacity required for Maximum Equipment (for example, assuming that
the wind load factor of Maximum Equipment is 100 and the wind load factor of
such New Equipment would be 50 and the Base Rent at such time is equal to $2,000
per month, the additional rent would be equal to $1,000 (50/100 times $2,000).
Notwithstanding the foregoing, in the event that the New Equipment that Lessee
elects to install upon any MATC Site pursuant to this Section 7(c) is (i) a
paging antenna, the additional rent to be paid by Lessee shall be four hundred
eighteen and 18/100 dollars (US$418.18) per set of omnidirectional and GPS
antenna, or (ii) one (1) additional microwave antenna (which does not exceed the
structural capacity required for a six foot diameter Andrew solid microwave
antenna) per Site, the additional rent to be paid by Lessee shall be two hundred
twelve and 18/100 dollars (US$212.18) per microwave antenna, each subject to a
three percent (3%) increase in such additional rate on each July 1 of each year
beginning on July 1, 2002. In the event the New Equipment that Lessee elects to
install upon any MATC Site is a microwave antenna in addition to the microwave
antenna permitted by the immediately preceding sentence, the Additional Rent to
be paid by Lessee per microwave antenna shall be calculated in accordance with
the formulas contained in Exhibit F attached hereto, as such Exhibit F may be
mutually amended from time to time. All Additional Rent pursuant to this Section
7(c) (but not pursuant to Section 5(c)) shall be subject to annual increases of
three percent (3%) on July 1 of each year beginning on July 1, 2002.

         (d)      Lessee shall timely pay for the electricity used in its
operations at the rate charged by the servicing utility company. Lessee shall
draw electricity by submeter and other utilities from the existing utilities on
the MATC Site, unless otherwise mutually agreed. Any easement necessary for such
power or other utilities will be at a location reasonably acceptable to MATC
Celular and the servicing utility company, but shall be subject to MATC
Celular's rights under the applicable Prime Lease.

         (e)      Lessee shall have the right to install or temporarily place,
as required, an emergency gasoline, butane, diesel or other fuel-powered
generator(s) on the Premises, at Lessee's sole cost and expense, and Lessee
covenants that such installation or placement and use shall be in compliance
with any applicable federal, state, or local environmental, health, fire,
community awareness, safety laws or other applicable laws or regulations, now or
hereafter enacted or promulgated by any governmental authority or court ruling
having jurisdiction over the relevant MATC Site, including,

                                      -14-

<PAGE>

without limitation, any applicable guidelines promulgated by the environmental
protection authorities.

         (f)      Lessee, Lessee's employees, agents and subcontractors may
                  enter on or across the MATC Site twenty four (24) hours a day,
seven (7) days a week, at no charge, to obtain entry into the Premises for the
purpose of constructing, installing, operating, maintaining and repairing those
parts of Lessee's Improvements and Equipment as are ground based, except as
otherwise expressly provided in the Prime Lease. Lessee shall not, without prior
notice to and approval (which shall not be unreasonably withheld or delayed)
from MATC Celular, perform or arrange to be performed normally scheduled
installation or repair of Lessee's Improvements and Equipment on a Tower. Any
emergency installation, maintenance or repair of Lessee's Improvements and
Equipment on the Tower shall be performed only with prior verbal notice to MATC
Celular. Such access shall be in accordance with the procedures set forth in
Exhibit D attached hereto, as such Exhibit D may be mutually amended from time
to time, and such access route shall be as shown in the applicable Site Lease.

         8.       NON-INTERFERENCE.

         In the event that the operations of Lessee (including any subsequent
modifications or installations) under any Site Lease interfere with the then
pre-existing transmitting or receiving of radio, television, or electronic
signals by MATC Celular or Other Tenants, Lessee shall cause the interference to
be eliminated within forty-eight (48) hours, for material interference, and
fifteen (15) Business Days if otherwise measurably adverse, at no cost to MATC
Celular or Other Tenants. In the event such interference does not cease within
such time period, MATC Celular may terminate the applicable Site Lease, or shut
off Lessee's Improvements and Equipment. This provision shall not apply to test
periods where the source of the interference is being determined for purposes of
suppression. In the event that, with respect to Lessee's initial installation,
any devices installed after Lessee's acceptance of a Completion Certificate for
any given Build-to-Suit Site or actual installation on any given MATC Existing
Site or, with respect to any subsequent modification of Lessee's Improvements
and Equipment or operations any devices installed after such modification shall
interfere with Lessee's then-existing transmission or reception, MATC Celular
shall cause the interference to be eliminated within forty-eight (48) hours, for
material interference, and fifteen (15) Business Days if otherwise measurably
adverse, at no cost to Lessee.

         In the event such interference does not cease within the time periods
specified above, the parties acknowledge that continuing interference will cause
irreparable injury to the party experiencing such interference and such party
shall have all rights available under applicable law to cause such interference
to cease.

         9.       TAXES.

         As provided in Section 5(c), Lessee shall pay to MATC Celular its Per
Capita Share (as defined in Section 5(c) hereof) of all real estate taxes and
other taxes, duties or charges of similar

                                      -15-

<PAGE>

nature imposed on the MATC Site. To that effect, MATC Celular shall make the
required calculations and inform Lessee the amounts payable together with any
supporting documentation. Lessee shall reimburse MATC Celular for any increases
in real property taxes that are assessed as a direct result of Lessee's
Improvements and Equipment to the MATC Sites. As a condition of Lessee's
obligation to pay such tax increases, MATC Celular shall provide Lessee the
documentation from the relevant taxing authorities indicating that the increase
is due to Lessee's Improvements and Equipment. Any other taxes, levies or rights
imposed by any authorities as a result of the performance of the obligations
under the Original Master Lease Agreement, this Master Lease or each Site Lease,
will be borne by the corresponding party, at its sole expense.

         10.      DEFAULT; TERMINATION.

         (a)      Either party shall be in default under an applicable Site
Lease if the party fails to perform any material duty or obligations under this
Master Lease or such Site Lease, in respect of a MATC Site or any Premises, and
does not cure or remedy such failure to perform within twenty (20) Business Days
after receipt of written notice with respect thereto; provided, however, that if
such failure to perform shall require a longer period to cure, then such cure
period shall be extended for such time as is reasonably necessary to cure such
failure to perform (not to exceed forty-five (45) Business Days), but only so
long as such efforts to cure are commenced within ten (10) Business Days after
receipt of written notice from the other party and thereafter proceed diligently
and in good faith. In the event that prior to Completion a Build-to-Suit Site is
terminated in accordance with the terms of the Build-to-Suit Agreement, the
associated Site Lease hereunder shall be deemed to have been terminated
contemporaneously. In the event that the applicable Tower Site Permits are
revoked or, with respect to a Build-to-Suit Site, the necessary Tower Site
Permits are not obtained prior to Completion of a Build-to-Suit Site, and as a
result thereof the applicable tower structure must be dismantled, the associated
Site Lease shall be deemed to have been terminated contemporaneously.
Notwithstanding the foregoing, in no event shall the time within which a party
may cure a failure in the payment of money exceed a single ten (10) Business Day
period following written notice of such failure, without extension; provided,
however, that the defaulting party shall be required to pay any overdue money
after such ten (10) Business Day period has elapsed by check and if such check
is accepted and deposited by the non-breaching party (so long as such check also
clears), then such deposit of the check shall be deemed a waiver by the
non-breaching party of such default.

         (b)      Upon the occurrence of a default, the non-defaulting party may
pursue any and all remedies available under applicable law and any one or more
of the following remedies, separately or concurrently or in any combination, to
the extent compatible under applicable law, without further notice or demand
whatsoever:

         (i)      Termination of the applicable Site Lease by giving the
                  defaulting party written notice of such termination, in which
                  event the applicable Site Lease shall be terminated at the
                  time designated in the notice; and

                                      -16-

<PAGE>

         (ii)     The recovery from the defaulting party of all damages, costs
                  and expenses incurred by the non-defaulting party in enforcing
                  and compensating its rights and remedies under this Master
                  Lease and the applicable Site Lease, including reasonable
                  attorneys' fees and expenses.

         (c)      Notwithstanding the foregoing, if Lessee breaches any of its
material obligations pursuant to ten (10) percent (10%) or more of the Site
Leases then in effect in any particular Region during any consecutive six (6)
month period during the Term, MATC Celular shall have the right to terminate
this Master Lease and any other or all of the Site Leases executed under the
terms of this Master Lease with respect to such Region; provided, however, that
if MATC Celular has previously exercised its right to accelerate the rental
payments due for the Region affected hereunder pursuant to Section 5(e) above,
MATC Celular shall not have the right to terminate the relevant Site Leases
which have been pre-paid.

         (d)      The termination of an applicable Site Lease by reason of a
party's default shall not relieve the defaulting party of any of its duties and
obligations accrued under this Master Lease in respect of such Site Lease or any
other Site Lease, prior to the effective date of such termination.

         (e)      At the expiration or termination of an applicable Site Lease
for any reason, Lessee shall surrender to MATC Celular the Premises, remove
Lessee's Improvements and Equipment, and shall restore the Premises to
substantially the same condition existing on the Commencement Date, except for
ordinary wear and tear. If Lessee fails to remove Lessee's Improvements and
Equipment as required, Lessee's Improvements and Equipment will, subject to
thirty (30) days prior written notice, be subject to disconnection, removal and
disposal by MATC Celular. In such event, Lessee will pay to MATC Celular upon
written demand therefor, the disconnection, removal and storage expenses
incurred by or on behalf of MATC Celular. If Lessee's Improvements and Equipment
are not claimed by Lessee within thirty (30) days following notice from MATC
Celular to Lessee of its removal, MATC Celular is hereby authorized by Lessee to
take any steps necessary, subject to any existing lien, security interest or
other encumbrance, to sell all or any portion of Lessee's Improvements and
Equipment, and Lessee shall execute any documents necessary to effect such
transfer. In the event Lessee's Improvements and Equipment remain on the
Premises following termination or expiration of this Master Lease (even if it
has been disconnected), Lessee shall pay to MATC Celular holdover rent equal to
one hundred and twenty-five percent (125%) of the then effective Base Rent,
prorated from the date of termination to the date Lessee's Improvements and
Equipment are removed from the Premises by Lessee. Notwithstanding anything to
the contrary herein, the notice requirements outlined in this Section 10(e)
shall not apply to the extent that they conflict with the provisions of the
applicable Prime Lease pursuant to its termination or expiration.

         (f)      In the event that MATC Celular commences construction of any
MATC Site prior to obtaining all required Tower Site Permits pursuant to Section
2.02 of the Build-to-Suit Agreement, then (a) with respect to Build-to-Suit
Sites, in MATC Celular's sole discretion and upon MATC Celular's written request
received by Lessee prior to the expiration of the Initial

                                      -17-

<PAGE>

Term (as defined in the Master Lease) of the applicable Site Lease, (i) Lessee
shall pay to MATC Celular all costs and expenses incurred by MATC Celular in
connection with the acquisition, development and construction of such
Build-to-Suit Site, including, if applicable, any cost associated with
dismantling any tower structure, if all applicable Tower Site Permits have not
been obtained, and (ii) MATC Celular and Lessee shall simultaneously execute any
necessary and customary documents, agreements, assignments and/or other
instruments by which title and rights to the Build-to-Suit Site (including,
without limitation, the tower structure, real property or leasehold interest,
and any tenant leases) are conveyed to Lessee; provided further, however, that
if MATC Celular can redeploy and reuse the tower structure or any other
materials at another site, then the costs and expenses for which Lessee shall be
responsible under this sentence shall be reduced accordingly, and (b) with
respect to MATC Existing Sites, in MATC Celular's sole discretion and upon MATC
Celular's written request received by Lessee prior to the expiration of the
Initial Term (as defined in the Master Lease) of the applicable Site Lease,
Lessee shall pay to MATC Celular all costs and expenses incurred by MATC Celular
in connection with the development and construction of such MATC Existing Site
to the extent that such costs were incurred directly in connection with the
development and preparation of the MATC Existing Site for the installation of
Lessee's Improvements and Equipment, including, if applicable, any cost incurred
by MATC Celular associated with removing Lessee's Improvements and Equipment if
all applicable Tower Site Permits have not been obtained, and MATC Celular and
Lessee shall simultaneously execute a termination of the applicable Site Lease.

         (g)      Upon no less than thirty (30) days prior written notice
(unless a lesser period of time is otherwise required by law), either party
hereto may terminate the applicable Site Lease without any further obligation by
either party to the other if any law, ordinance, regulation or directive of any
governmental or regulatory authority hereinafter enacted or ordered prohibits
Lessee's or MATC Celular's use of the Premises so long as such governmental
action is not the result of any action or inaction by the terminating party;
provided, however, that any termination hereunder due to MATC Celular's election
to construct the associated antenna structure prior to obtaining the necessary
Tower Site Permits shall not be deemed an action or inaction on the part of MATC
Celular (which would otherwise prohibit MATC Celular's right to terminate the
affected Site Lease hereunder) so long as MATC Celular notified Lessee in the
applicable Site Lease that all necessary Tower Site Permits have not been
obtained for the associated MATC Existing Site or, in the event of a
Build-to-Suit Site, such construction was pursuant to Section 2.02 of the BTS
Agreement.

         (h)      MATC Celular will provide Lessee with a copy of any notice of
default received by MATC Celular under any Prime Lease in the event that MATC
Celular does not intend to or can not cure any such default during the
applicable cure period provided for in the Prime Lease or of any notice,
complaint, order or decree that will (or could) adversely affect Lessee's
ability to operate its wireless communications from the Site or will (or could)
adversely affect any right or remedy of Lessee hereunder. Any failure by MATC
Celular to deliver notice pursuant to this Section shall not be deemed a default
under this Agreement so long as Lessee does not suffer any materially adverse
consequence as a result thereof.

                                      -18-

<PAGE>

         (i)      Notwithstanding anything to the contrary in this Agreement, in
the event that MATC Celular fails to comply with the provisions of a Prime
Lease, any governmental requirements, or its maintenance or repair obligations
hereunder and Lessee's rights hereunder shall (or could) be materially and
adversely affected by a failure to comply, Lessee (in addition to any other
rights and remedies it may be entitled to hereunder) will be authorized,
following no less than five (5) Business Days prior written notice to MATC
Celular (unless during such period MATC Celular diligently commences and pursues
the cure of such failure), to pay any reasonable amount required to cure such
failure or, if applicable, commence and prosecute any and all reasonable action
or actions necessary to cure such failure as may be available to MATC Celular.
Following any such payment by Lessee, Lessee will be entitled to withhold the
full amount thereof from installments of rent or other payments next owing under
this Agreement until such amount and charge have been fully credited.

         11.      EXPROPRIATION.

         If the whole or any substantial part of an MATC Site shall be taken by
any public authority under the power of eminent domain (expropiacion) so as to
materially interfere with Lessee's use and occupancy, then the Site Lease shall
terminate as to such MATC Site so taken. Any Base Rent paid in advance shall be
refunded to Lessee within thirty (30) days of Lessee's written demand.

         12.      INSURANCE.

         (a)      Each Party shall carry during the term of each Site Lease, at
its own cost and expense, the following insurance with respect to the MATC Sites
and the Premises: (i) "All Risk" property insurance which insures the insuring
party's property for its full replacement cost; and (ii) comprehensive general
liability insurance with a commercial general liability endorsement having a
minimum limit of liability of US$1,000,000.00 (one million Dollars 00/100 U.S.
Cy.) with a combined limit for bodily injury and/or property damage for any one
occurrence, and (iii) excess/umbrella coverage of US$5,000,000.00 (five million
Dollars 00/100 U.S. Cy.). MATC Celular agrees to use its reasonable best efforts
to require all Other Tenants who execute lease agreements with MATC Celular on
or after the date first written above to maintain insurance coverage comparable
(based on such Other tenant's equipment installation and use of a Site) to the
coverage limits set forth in this Section 12(a).

         (b)      Each Party shall name the other as an additional insured under
its liability policy and require its insurance company to endeavor to give at
least thirty (30) days' written notice of termination or cancellation of the
policy to the additional insured. A certificate of such insurance, together with
such endorsement, shall be delivered to the additional insured within thirty
(30) days from the Commencement Date for each Site Lease and before the
expiration of any term thereof, from a licensed insurance company. All insurance
certificates must contain an undertaking by the agents or brokers to notify the
other party in writing not less than thirty (30) days before any material
change, reduction in coverage, cancellation or termination of the insurance.

                                      -19-

<PAGE>

         (c)      Lessee shall cause any contractor retained by Lessee to
maintain in full force and effect during the term of any maintenance, work or
repairs performed on Lessee's behalf at any MATC Site, insurance satisfying the
coverage requirements described in Section 12(a) and to deliver, prior to the
commencement of such work, an insurance certificate naming MATC Celular as an
additional insured. Notwithstanding the foregoing, MATC Celular reserves the
right to refuse to permit any person or company to climb any Tower. Lessee shall
be solely responsible and liable to MATC Celular for Lessee's failure to obtain
or deliver to MATC Celular the required insurance certificates from Lessee's
approved contractor.

         13.      ASSIGNMENT.

         (a)      This Master Lease or any Site Lease may be sold, assigned or
transferred, in whole or in part, by MATC Celular (i) to any subsidiary and/or
affiliate of MATC Celular; (ii) in the event of a sale, assignment or transfer
of all or substantially all of MATC Celular's assets or stock in one or a series
of related transactions; (iii) in the event of a sale, assignment or transfer of
all or substantially all of MATC Celular's assets located within a particular
Region (as such regions are defined in Section 13(b) below), and (iv) pursuant
to any sale or transfer of any of MATC Celular's parent companies, or the
mergers or corporate reorganizations of such parent companies. Any other
assignment of this Master Lease or any Site Lease shall require the prior
written consent of Lessee, which consent shall not be unreasonably withheld,
conditioned or delayed

         (b)      This Master Lease or any Site Lease may not be sold, assigned
or transferred, in whole or in part, by Lessee without prior approval or consent
of MATC Celular; provided, however, that notwithstanding anything to the
contrary contained herein, Lessee may sublease any space on the Premises,
transfer any of its rights and/or obligations under this Master Lease, Lessee's
Improvements and Equipment and/or any Site Lease (i) to any subsidiary and/or
Affiliate whose ownership or voting percentage is not modified to less than
forty-five percent (45%) by any act or series of acts subsequent to the
assignment that may cause Lessee to lose such percentage within two (2) years
from the date of the assignment, provided that the respective permitted
sublessee or assignee must execute a Joinder Agreement in the form of Exhibit E,
before taking possession of the subleased Premises; (ii) in the event that such
sale, assignment or transfer is associated with the sale of all or substantially
all of Lessee's assets located within a particular Mexican Region (as such
regions are commonly defined with respect to communication services as of the
date of the execution of this Master Lease and hereinafter referred to as a
"REGION(S)"), or (iii) pursuant to any sale or transfer of any of Lessee's
parent companies, or the mergers or corporate reorganizations of such parent
companies. MATC Celular may not unreasonably withhold, condition or delay such
consent. In no event may Lessee sublease, sublicense, or permit shared use of
the Premises by any party other than an Affiliate of Lessee in accordance with
subsection 13(b)(i) herein; provided, however, that in the event that the
applicable antenna structure is fully loaded and can not be structurally
modified to accommodate any additional equipment, Lessee may sublease or
sublicense the Premises to a

                                      -20-

<PAGE>

third party with the prior written consent of MATC Celular, which consent shall
not be unreasonably withheld or delayed.

         (c)      Notwithstanding the foregoing, Lessee may, upon prior written
notice to MATC Celular, mortgage or grant a security interest in Lessee's
Improvements and Equipment to any bona fide unaffiliated institutional lender in
connection with any bona fide financing by Lessee, and may assign its rights to
Lessee's Improvements and Equipment to any such mortgagees or holders of
security interests including their successors or assigns (hereinafter
collectively referred to as "LESSEE MORTGAGEES"). In such event, MATC Celular
shall execute such consent to leasehold financing as may reasonably be required
by Lessee Mortgagees, in which MATC Celular will agree to notify Lessee and the
Lessee Mortgagees simultaneously of any default by Lessee and to give Lessee
Mortgagees the same right to cure any default as Lessee except that the cure
period for any Lessee Mortgagee shall not be less than ten (10) days after
receipt of the default notice.

         14.      WARRANTY OF TITLE AND QUIET ENJOYMENT; COMPLIANCE WITH LAWS.

         (a)      MATC Celular warrants that: (i) MATC Celular will own or lease
the MATC Site and the structure located thereon (if any) and will have rights of
access thereto; (ii) MATC Celular has full right to make and perform this Master
Lease; and (iii) MATC Celular covenants and agrees with Lessee that, according
to article 2412 of the Civil Code for the Federal District and the applicable
provisions of the Civil Codes of the jurisdictions where any MATC Site is
located, upon Lessee paying the Base Rent and Additional Rent and observing and
performing all the material terms, covenants and conditions on Lessee's part to
be observed and performed, Lessee may peacefully and quietly have, hold and
enjoy possession and use of the Premises; provided, however, that MATC Celular
shall not be deemed to have breached any warranty provided in this Section 14 to
the extent such breach is a result of MATC Celular commencing with construction
of a MATC Site prior to obtaining all necessary Permits.

         (b)      In the performance by each party to this Agreement of its
respective obligations hereunder, the parties recognize and acknowledge that
each party hereto shall be responsible for the personnel it employs to perform
its respective obligations hereunder, including, without limitation, their
ordinary and extraordinary salaries, vacations, Christmas bonus (aguinaldo),
seniority payments (prima de antiguedad), disability payments, severance
payments, contributions to the IMSS and INFONAVIT and any other existing
obligation derived from the Federal Labor Law (Ley Federal de Trabajo)
(collectively, "LABOR OBLIGATIONS"). Each party shall have no responsibility for
the other party's Labor Obligations or to the other party's personnel or
otherwise, and each party agrees to indemnify, defend and hold harmless the
other party and its respective Affiliates, and their directors, officers and
employees, from and against all Losses based upon any claim arising out of Labor
Obligations. In the performance by the parties of their respective obligations
under this Agreement, each of MATC Celular and Lessee agree to comply with any
and all applicable laws of Mexico and, as applicable, the United States. Without
limiting the generality of the foregoing, MATC Celular and Lessee each agree, in
the

                                      -21-

<PAGE>

performance of their respective obligations hereunder, to comply with the
provisions of the Foreign Corrupt Practices Act of the United States.

         15.      MAINTENANCE AND REPAIRS.

         (a)      Lessee shall perform all repairs necessary or appropriate to
keep Lessee's Improvements and Equipment on or about the Premises or located on
any appurtenant rights-of-way or access to the Premises in good and tenantable
condition. Damage to Lessee's Improvements and Equipment resulting from the acts
or omissions of MATC Celular shall be repaired by MATC Celular, at MATC
Celular's cost and expense unless otherwise provided herein.

         (b)      MATC Celular, at MATC Celular's sole cost and expense, shall
maintain the MATC Sites and its improvements thereto in good order and repair,
except acts resulting from act of god or force majeure (caso fortuito o fuerza
mayor) which shall be repaired by MATC Celular as promptly as is practical under
the circumstances; provided, however, that if Lessee's ability to provide
service to its customers through Lessee's Improvements and Equipment is
negatively affected, MATC Celular shall commence the repair of the facilities
within twenty-four (24) hours and shall complete such repairs within the time
period reasonably necessary to effect such repairs under the circumstances)
following written notice from Lessee thereof. Notwithstanding the foregoing,
MATC Celular shall have no obligation to maintain or repair air conditioners
provided pursuant to the Build-to-Suit Agreement. Damage resulting from the acts
or omissions of Lessee shall be repaired by Lessee, at Lessee's cost and expense
unless otherwise provided herein.

         16.      MISCELLANEOUS.

         16.01    ENTIRE AGREEMENT. This Master Lease and the applicable Site
Lease constitute the entire agreement and understanding between the parties, and
supersedes all offers, negotiations and other agreements concerning the subject
matter contained herein. Any amendments to this Master Lease or any Site Lease
must be in writing and executed by both parties.

         16.02    SEVERABILITY. If any provision of this Master Lease is invalid
or unenforceable with respect to any party, the remainder of this Master Lease
or the application of such provision to persons other than those as to whom it
is held invalid or unenforceable, shall not be affected and each provision of
this Master Lease shall be valid and enforceable to the fullest extent permitted
by law.

         16.03    BINDING EFFECT. This Master Lease shall be binding on and
inure to the benefit of the successors and permitted assignees of the respective
parties.

         16.04    NOTICES. Any notice or demand required to be given herein
shall be made by recognized overnight courier to the address of the respective
parties set forth below:

                                      -22-

<PAGE>

         LESSEE:
                               Grupo Iusacell Celular, S.A. de C.V.,
                               Prol. Paseo da la Reforma 1236, 4th Floor
                               Col. Santa Fe, 05348 Mexico, D.F.
                               Attention: Vice President/Technical Operations
                               Fax No.:  (011) (525) 109-5407

         With a copy to:       Grupo Iusacell Celular, S.A. de C.V.
                               Prol. Paseo da la Reforma 1236, PH
                               Col. Santa Fe, 05348 Mexico, D.F.
                               Attention: General Counsel
                               Fax No.:  (011) (525) 109-5772

         MATC CELULAR:         MATC Celular, S. de R.L. de C.V.
                               Av. Paseo de la Reforma, 350
                               Col. Lomas de Chapultepec
                               Mexico City, Mexico
                               Attention: Kevin Corrigan
                               Fax No.: (011) (525) 240-2026

         With a copy to:       American Tower Corporation
                               116 Huntington Avenue
                               Boston, MA 02116
                               Attention: Bob Kellegrew, Esq.
                               Fax No.: (617) 375-7575

                               - and-

                               American Tower International
                               3200 Cobb Galleria Parkway, Suite 205
                               Atlanta, Georgia 30339
                               Attention: Dan Brooks
                               Fax No.: (770) 952-4999

         MATC Celular or Lessee may from time to time designate any other
address for this purpose by written notice to the other party. All notices
hereunder shall be deemed received upon actual receipt.

         16.05    GOVERNING LAW. This Master Lease shall be governed, to the
extent applicable, by the Civil Code for the Federal District (of general
application in federal matters) and other applicable federal laws of the United
Mexican States ("Mexico"). The Site Leases shall be governed by the laws of the
jurisdiction on which the corresponding MATC Sites are located, as specified in
each Site Lease.

                                      -23-

<PAGE>

         16.06    [INTENTIONALLY OMITTED]

         16.07    COUNTERPARTS. All Exhibits to this Master Lease or any Site
Lease may be executed in duplicate counterparts, each of which shall be deemed
an original. This Master Lease and any Site Lease may be executed in as many
counterparts as the parties deem necessary, each of which shall be deemed an
original.

         16.08    LANGUAGE. This Master Lease is executed and each Site Lease
will be executed in the English language; provided, however, that the parties
hereto hereby irrevocably agree and accept that the Spanish translation of this
Agreement attached hereto as Exhibit "C", is a true, accurate and complete
translation of this Agreement that shall be used in the event that any party
hereto brings a legal action or proceeding with respect to this Agreement and
the parties hereto hereby waive any right to challenge the validity,
truthfulness, accuracy or completeness of such Spanish translation.

         17.      TOWER MARKING AND LIGHTING REQUIREMENTS.

         For each MATC Site, MATC Celular shall be responsible for compliance
with all marking and lighting requirements under applicable laws and regulations
in Mexico, provided that if the requirement for compliance results from Lessee's
Improvements and Equipment, Lessee shall pay for the reasonable costs and
expenses therefor.

         18.      INDEMNITY.

         (a)      Each party hereto ("INDEMNIFYING PARTY") agrees to compensate
the other party for damages and to defend, indemnify and to hold the other party
harmless from all claims (including reasonable attorneys' fees, costs and
expenses of defending against such claims) incurred and arising from the
negligent acts or omissions of the Indemnifying Party or its agents, employees,
engineers, contractors, subcontractors, or invitees in or about the Premises or
arising from the Indemnifying Party's default pursuant to this Master Lease or
the applicable Site Lease. Except as otherwise specifically provided herein to
the contrary, it is understood and agreed that all property kept, installed,
stored, or maintained in or upon the Premises by Lessee shall be so installed,
kept, stored, or maintained at Lessee's risk. Neither party hereto shall be
responsible for any loss or damage to equipment owned by the other party which
might result from tornadoes, lightning, wind storms, hail, flying debris, or
other acts of God (caso fortuito o fuerza mayor). The indemnities described in
this Section shall survive termination of this Master Lease or the applicable
Site Lease.

         (b)      Notwithstanding any provision of this Master Lease to the
contrary (other than Section 5 hereof), each party hereby waives the right to
recover consequential (including lost profits), punitive, exemplary and similar
damages and the multiplied portion of damages except to the extent such damages
are suffered by such party in connection with an action initiated by a third
party.

                                      -24-

<PAGE>

         19.      HAZARDOUS SUBSTANCES.

         Lessee agrees that it will not use, generate, store or dispose of any
hazardous material on, under, about or within the MATC Sites in violation of any
law or regulation. MATC Celular represents, warrants and agrees (i) that neither
MATC Celular nor, to MATC Celular's knowledge, any third party has used,
generated, stored or disposed of, or permitted the use, generation, storage or
disposal of, any hazardous material on, under, about or within the Build-to-Suit
Sites in violation of any law of regulation, unless otherwise disclosed in the
applicable Site Lease and (ii) that MATC Celular will not generate, store or
dispose of any hazardous material on, under, about or within the MATC Sites in
violation of any law or regulation. MATC Celular and Lessee each agree to
defend, indemnify and hold harmless the other party and the other party's
partners, affiliates, agents and employees against any and all losses,
liabilities, claims and/or costs (including reasonable attorneys' fees and
costs) arising from any breach of any representation, warranty or agreement
contained in this Section. As used in this Section 19, "Hazardous Material"
shall mean petroleum or any petroleum product, asbestos, and/or any substance,
chemical or waste that is identified as hazardous, toxic or dangerous in any
applicable federal, state or local law or regulation. This Section shall survive
the termination of this Master Lease.

         20.      REPLACEMENT OR RECONSTRUCTION OF TOWER BY MATC CELULAR.
Notwithstanding anything to the contrary contained herein, Lessee acknowledges
and agrees that MATC Celular reserves the right to replace or rebuild an
existing structure or the top of any structure upon no less than sixty (60) days
prior written notice to Lessee, provided, however, that in the event of such
replacement, MATC Celular shall provide Lessee with suitable space at the MATC
Site during the construction period to permit the continued operation of
Lessee's Improvements and Equipment and MATC Celular shall be solely responsible
for the costs associated with removing and re-installing the Lessee's
Improvements and Equipment on the replacement structure. MATC Celular also
expressly reserves the right to erect one or more towers on the MATC Site,
subject to MATC Celular's obligations to Lessee pursuant to Section 8 of this
Master Lease. In no event shall Lessee's Base Rent be abated in any manner
during any period of construction of the Tower or candelabra so long as Lessee
is capable of continuing to operate its equipment from a temporary location on
the MATC Site. Lessee acknowledges and agrees that it will reasonably cooperate
with MATC Celular in any actions, filings, or permits which may be required for
MATC Celular to exercise its rights under this Section 20. In the event that the
replacement space provided to Lessee fails to meet Lessee's RF standards, Lessee
shall reserve the right to terminate the applicable Site Lease upon thirty (30)
days notice to MATC Celular without any further obligation of either party to
the other hereunder.

         21.      CONFIDENTIALITY. The parties agree to hold the economic terms
and conditions of this Agreement in strict confidence, and shall bind its
employees, affiliates, advisors, representatives and agents to keep such
economic terms in strict confidence, and not to make any disclosure with respect
thereto, publicly or privately, other than as is jointly agreed to by the
parties or as is required by applicable law (of any applicable country),
including the rules and

                                      -25-

<PAGE>

regulations of the Mexican National Banking and Securities Commission, the
Securities and Exchange Commission, and the stock exchange rules or regulations.
If a public statement by either party is determined to be required by law or
stock exchange rules or regulations, the other party shall have the right to
review and comment on such statement prior to its release to the extent
practicable. Except as otherwise provided above, without the prior written
consent of the other party, no party shall at any time disclose any such
economic terms to any third party not bound by the confidential duty. The
provisions contained herein shall survive termination of this Agreement and
shall remain in full force and effect for a term of five (5) years after
termination of this Agreement.

         22.      DISPUTE RESOLUTION.

         A.       Master Lease.

         Any dispute among the parties hereto shall be resolved in accordance
with the arbitration provisions of this Section:

         (a)      Any party may give the other written notice that a dispute
exists (a "NOTICE OF DISPUTE"). The Notice of Dispute shall include a statement
of such party's position. All documents and other information or data on which
each party relies concerning the dispute shall be furnished or made available on
reasonable terms to the other party.

         (b)      Prior to initiating the arbitration proceedings described in
paragraph (c) below, either party to this Agreement may call a special meeting
for the resolution of a dispute and such meeting shall be held at a mutually
agreeable location within twenty (20) Business Days of a written request, which
request shall specify in reasonable detail the nature of the dispute to be
resolved at the meeting. The meeting shall be attended by representatives of the
parties to the Agreement and such representatives shall attempt in good faith to
resolve the dispute. If the dispute has not been resolved within five (5)
Business Days after the special meeting has been held, a senior corporate
manager of Lessee and MATC Celular, each with full authority to settle the
dispute, shall meet and attempt in good faith to resolve the dispute within ten
(10) Business Days after the initial special meeting.

         (c)      Any controversy or claim arising out of or relating to this
Master Lease and/or the breach, termination or validity thereof, or the
transactions contemplated herein, if not settled by negotiation as set forth in
subsection (b) above, shall be settled by arbitration in the city of Mexico
City, Mexico, in accordance with the American Arbitration Association Rules for
Commercial Disputes, by three arbitrators, two of which will be appointed by the
parties and the third arbitrator to be appointed by the arbitrators so
appointed, or if no consent is reached, by the American Arbitration Association
under applicable rules. The arbitration proceedings shall be conducted in the
English language in accordance with the arbitration rules of the American
Arbitration Association. The award rendered by the arbitrators shall be final
and binding on the parties and may be entered in any court having jurisdiction
thereof.

                                      -26-

<PAGE>

         (d)      It is the intent of the parties that any arbitration shall be
concluded as quickly as reasonably practicable. Unless the parties otherwise
agree once commenced, the hearing on the disputed matters shall be held four
days a week until concluded, with each hearing date to begin at 9:00 a.m. and to
conclude at 5:00 p.m. The arbitrators shall use all reasonable efforts to issue
the final award or awards within a period of five (5) business days after
closure of the proceedings. Failure of the arbitrators to meet the time limits
of this subsection shall not be a basis for challenging the award.

         (d)      The arbitrators shall instruct the non-prevailing party(ies)
to pay all costs of the proceedings, including the fees and expenses of the
arbitration and the reasonable attorneys' fees and expenses of the prevailing
party(ies). If the arbitrators determine that there is not a prevailing party,
each party shall be instructed to bear its own costs and to pay one-half of the
fees and expenses of the arbitrators.

         B.       Site Leases.

         For everything exclusively and specifically related to any particular
Site Lease, the breach, termination or validity thereof, or the transactions
contemplated therein or any legal action or proceeding with respect thereto, the
parties hereto expressly and irrevocably submit to the jurisdiction of the
competent courts of the jurisdiction in which the relevant MATC Site is located,
and by the execution and delivery of this Master Lease, each of the parties
hereto expressly and irrevocable waives the jurisdiction of any other court to
which they may be entitled by reason of their respective present or future
domiciles or for any other reason.

                                      -27-

<PAGE>

         IN WITNESS WHEREOF, the parties have executed this Master Lease as of
the date first above written.

         GRUPO IUSACELL CELULAR, S.A. DE C.V.

         By: /s/ Peter H. Burrowes
             ________________________________
         Name:  Peter H. Burrowes
         Title: President and General Director

         MATC CELULAR, S. DE R.L. DE C.V.

         By: /s/ J. Michael Gearon
             ________________________________
         Name:  J. Michael Gearon
         Title: Attorney-in-Fact

                                      -28-

<PAGE>

                                    EXHIBIT A

                   AMENDED & RESTATED BUILD-TO-SUIT AGREEMENT

<PAGE>

                                   EXHIBIT B-1
                   FORM OF SITE LEASE FOR BUILD-TO-SUIT SITES

 [This is intended by the parties hereto to be a sample, which shall be modified
        by the mutual agreement of the parties hereto, from time to time]

                                                                   [Date]
[LESSEE]

Attention Mr._________________

         This Site Lease is issued by MATC Celular, S. de R.L. de C.V. ("MATC
Celular") under terms of that certain Amended and Restated Master Lease
Agreement (the "Master Lease") dated May 16, 2002, entered into by and between
MATC Celular and Grupo Iusacell Celular, S.A. de C.V. ("Lessee").

         Terms not otherwise defined herein shall have the meaning assigned to
them in the Master Lease or the Amended and Restated Build to Suit Agreement, of
even date, entered into by and between MATC Celular and Lessee (the "Build to
Suit Agreement").

         [IF APPLICABLE: A COPY OF THE PRIME LEASE RELATING TO THE MATC SITE
COVERED BY THIS SITE LEASE IS ATTACHED TO THIS SITE LEASE AS ATTACHMENT A.]

SECTION 1. TOWER INFORMATION:

         Tower Name:             ______________            Coordinates: _______
         Tower Number:           ______________
         City, State and Region: ______________________________________________
         This Site is a Build-to-Suit Site

SECTION 2. RENT AND TERM:

         (a)      Commencement Date: The Commencement Date of this Site Lease
                  shall be the first to occur of (A) the date specified in the
                  Completion Certificate if accepted by Lessee or Lessee issues
                  a Provisional Acceptance Notice, or (B) the date of expiration
                  of the Inspection Term, as specified in Section 4.03 of the
                  Build-to-Suit Agreement.

         (b)      Base Rent: The initial Base Rent, calculated in accordance
                  with Section 5 of the Master Lease, shall be
                  US$________________________, plus value added tax. Base Rent
                  shall be due and payable in accordance with Section 5(d) of
                  the Master Lease and shall be adjusted from time to time in
                  accordance with the provisions of the Master Lease, including
                  without limitation, Section 5(b) thereof.

<PAGE>

         (c)      Additional Rent: The initial Additional Rent shall be the
                  amount calculated based on the Initial Equipment Description
                  and Lessee's Per Capita Share, plus value added tax.
                  Additional Rent shall be adjusted from time to time in
                  accordance with the provisions of the Master Lease, including,
                  without limitation, Section 5(b), 5(c) and 7(c) thereof.

         (d)      Lessee's Per Capita Share shall be calculated pursuant to
                  Section 5(c) of the Master Lease.

         (e)      Refer to Section 4 of the Master Lease for the duration of the
                  Term (including renewal periods) and Section 5 of the Master
                  Lease for the annual escalation of the Rent. The provisions of
                  Section 5 of the Master Lease shall apply to all matters
                  related to the Rent and not expressly provided for herein.

SECTION 3. LOCATION/IDENTIFICATION OF PREMISES

                  Height of Center of Radiation for RF Antennas (center point of
                  20 foot expanse comprising the "Premises"):___________________

SECTION 4. LESSEE'S IMPROVEMENTS AND EQUIPMENT INFORMATION:

         (a)      The Initial Equipment Description, presented by Lessee in
                  connection with this Site and duly signed by the parties, is
                  attached hereto as Attachment B (the "Initial Equipment
                  Description").

         (b)      Lessee shall deliver to MATC Celular, within a term of thirty
                  (30) calendar days as of the Commencement Date, the Final
                  Equipment Report that contains the information set forth in
                  Attachment C hereto (the "Final Equipment Report"). Any
                  equipment in excess of the Structural Capacity required for
                  the Maximum Equipment or located outside the Premises will be
                  subject to Additional Rent. The Final Equipment Report
                  furnished by Lessee will not bind MATC Celular, unless
                  accepted in writing by MATC Celular, and the acceptance
                  thereof shall not constitute a waiver by MATC Celular of any
                  of its rights or remedies under this Site Lease or the Master
                  Lease. The parties agree that upon preparation by the Lessee
                  and delivery to MATC Celular of the Final Equipment Report,
                  said report, duly signed by the parties, shall be added to and
                  become part of this Site Lease.

         (c)      During the period beginning on the Commencement Date and
                  ending on the earlier of (i) Lessee's delivery of the Final
                  Equipment Report to MATC Celular, and (ii) thirty (30) days
                  after the Commencement Date (the "Installation Period"),
                  Lessee may install Lessee's Improvements and Equipment.
                  Lessee's Improvements and Equipment installed during the
                  Installation Period may not exceed the Structural Capacity
                  required for the Maximum Equipment, nor may it be located
                  outside of the Premises.

                                       -2-

<PAGE>

         (d)      In the event Lessee does not furnish the Final Equipment
                  Report to MATC Celular within the thirty (30)-day term
                  referred to in paragraph (b) above, MATC Celular shall have
                  the right, to perform all actions it deems appropriate to
                  gather the information that the Final Equipment Report shall
                  contain. Lessee hereby agrees to reimburse to MATC Celular,
                  within thirty (30) days following receipt of the corresponding
                  invoice from MATC Celular, all costs and expenses incurred by
                  MATC Celular for the preparation and completion of the Final
                  Equipment Report and the obtaining of the information
                  necessary to that effect, and further agrees to pay to MATC
                  Celular, liquidated damages resulting from the failure to
                  deliver the Final Equipment Report referred to above, in an
                  amount equal to 25% (twenty five per cent) of the total amount
                  of said costs and expenses, which shall be duly documented.

         (e)      If a Final Equipment Report is provided by Lessee in
                  accordance with Section 4(b), the Additional Rent payable
                  pursuant to this Site Lease shall be adjusted, beginning on
                  the date on which the Equipment Report is delivered to MATC
                  Celular, to account for the additional equipment listed in the
                  Final Equipment Report. If MATC Celular exercised its rights
                  to gather information pursuant to Section 4(d), MATC Celular
                  shall be entitled to adjust the Additional Rent payable by
                  Lessee, based on the results of the information gathered
                  pursuant to such Section 4(d), retroactively to the date on
                  which the Final Equipment Report was due hereunder, and Lessee
                  shall pay such additional amount within five (5) calendar days
                  following receipt of an invoice from MATC Celular. If a Final
                  Equipment Report is not provided pursuant to Section 4(b) and
                  MATC Celular does not exercise its rights pursuant to Section
                  4(d), Additional Rent shall continue to be based on the
                  information provided in the Initial Equipment Description,
                  subject to Section 6.

SECTION 5. RENT AND TERM TO INSTALL NEW EQUIPMENT AND MICROWAVE EQUIPMENT

         (a)      In the event that after the expiration of the Installation
                  Period, Lessee wishes to install Improvements and Equipment
                  outside of the Premises or exceeding the Base Capacity in
                  accordance with Section 7(c) of the Master Lease, such
                  Lessee's Improvements and Equipment shall be considered as New
                  Equipment.

         (b)      In the event that Lessee wishes to install equipment
                  considered as New Equipment, Lessee shall deliver to MATC
                  Celular, a request in the form established by MATC Celular to
                  that effect, MATC Celular and Lessee shall enter into a new
                  Site Lease, in accordance with the terms of the Master Lease,
                  including without limitation Section 7(c).

SECTION 6. DEFAULT DUE TO INSTALLATION OF NEW EQUIPMENT

                                       -3-

<PAGE>

In the event that MATC Celular finds, through a Site audit, additional equipment
to that set forth in the Equipment Report or in the Initial Equipment
Description (or in the event the Equipment Report has not been delivered to MATC
Celular pursuant to Section 4(b) and MATC Celular has not exercised its rights
pursuant to Section 4(d)) ("Non-Reported Equipment"), MATC Celular may, at its
discretion, exercise its rights under the Master Lease and/or cause Lessee to
pay Base Rent and Additional Rent for the Not Reported Equipment, from the
Commencement Date, plus any late fees applicable pursuant to the Master Lease,
plus an amount equal to twenty-five percent (25%) of the Base Rent and
Additional Rent as liquidated damages.

SECTION 7. INTERPRETATION

In the event of doubts in the interpretation or conflict between the provisions
of this Site Lease and the Master Lease, the provisions of the Master Lease
shall prevail.

         [INFORMATION SIMILAR TO THAT PROVIDED ABOVE SHALL BE PROVIDED FOR ALL
         MICROWAVE AND PAGING EQUIPMENT INSTALLED ON THE SITE, AS APPLICABLE]

SITE DRAWINGS/STRUCTURALS (IF ANY) ARE ATTACHED TO THIS EXHIBIT B-1 AS
ATTACHMENT D.

Disclosure of environmental conditions required pursuant to Section 19 of the
Master Lease:

________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

         Upon signature of this Site Lease, the Lessee agrees to be bound by the
provisions of the Master Lease. Any of the parties may cause this Site Lease and
the Master Lease to be registered at the Public Registry of Property of the
location of the Premises, as specified above.

_______________________________                 MATC Celular, S. de R.L. de C.V.

_______________________________                 ________________________________
By:                                             By:
Position:                                       Position:
Date:                                           Date:

                                       -4-

<PAGE>

              Attachment A to Exhibit B-1, Build to Suit Site Lease

                              Copy of Ground Lease

                                       -5-

<PAGE>

              Attachment B to Exhibit B-1, Build to Suit Site Lease

                          Initial Equipment Description

                                       -6-

<PAGE>

              Attachment C to Exhibit B-1, Build to Suit Site Lease

                           Final Equipment Description

         LESSEE'S IMPROVEMENTS AND EQUIPMENT TO BE INSTALLED ON TOWER:

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------
                                      #1                #2                #3                    #4
-----------------------------------------------------------------------------------------------------------
<S>                                   <C>               <C>               <C>                   <C>
QUANTITY:
-----------------------------------------------------------------------------------------------------------
MANUFACTURER:
-----------------------------------------------------------------------------------------------------------
TYPE & MODEL #:
-----------------------------------------------------------------------------------------------------------
ANTENNA WEIGHT/LENGTH:
-----------------------------------------------------------------------------------------------------------
LINE TYPE:
-----------------------------------------------------------------------------------------------------------
LINE QUALITY & DIAMETER:
-----------------------------------------------------------------------------------------------------------
ANTENNA MOUNT HEIGHT
-----------------------------------------------------------------------------------------------------------
TOWER LEG:
-----------------------------------------------------------------------------------------------------------
DIRECTION OF RADIATION:
-----------------------------------------------------------------------------------------------------------
REQUESTED MOUNTING POSITION:
-----------------------------------------------------------------------------------------------------------
</TABLE>

         TRANSMISSION AND OTHER EQUIPMENT TO BE LOCATED IN LESSEE'S EQUIPMENT
         BUILDING:

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------------------------------
                                      #1                #2                #3                #4
-------------------------------------------------------------------------------------------------------
<S>                                   <C>               <C>               <C>               <C>
NUMBER OF CABINETS:
-------------------------------------------------------------------------------------------------------
# OF TRANSMITTERS PER
CABINET:
-------------------------------------------------------------------------------------------------------
MANUFACTURER:
-------------------------------------------------------------------------------------------------------
TYPE & MODEL #:
-------------------------------------------------------------------------------------------------------
TYPE OF SERVICE:
-------------------------------------------------------------------------------------------------------
RACK DIMENSIONS:
-------------------------------------------------------------------------------------------------------
RATED POWER:
-------------------------------------------------------------------------------------------------------
CALL SIGN:
-------------------------------------------------------------------------------------------------------
TX FREQUENCY:
-------------------------------------------------------------------------------------------------------
RX FREQUENCY:
-------------------------------------------------------------------------------------------------------
ELEC. SERVICE AMPS/VOLTS:
-------------------------------------------------------------------------------------------------------
NUMBER OF OUTLETS:
-------------------------------------------------------------------------------------------------------
POWER OUTLETS:
-------------------------------------------------------------------------------------------------------
ERP:
-------------------------------------------------------------------------------------------------------
DIMENSIONS (W" X D" X H")
-------------------------------------------------------------------------------------------------------
COMBINER/# OF PORTS:
-------------------------------------------------------------------------------------------------------
CABINET ALSO CONTAINS:
-------------------------------------------------------------------------------------------------------
GROUND SPACE DIMENSION (IF
APPL):
-------------------------------------------------------------------------------------------------------
</TABLE>

         [INFORMATION SIMILAR TO THAT PROVIDED ABOVE SHALL BE PROVIDED FOR ALL
         MICROWAVE AND PAGING EQUIPMENT INSTALLED ON THE SITE, AS APPLICABLE]

                                       -7-

<PAGE>

              Attachment D to Exhibit B-1, Build to Suit Site Lease

                            Site Drawings/Structurals

                                       -8-

<PAGE>

                                   EXHIBIT B-2
                   FORM OF SITE LEASE FOR MATC EXISTING SITES

[This is intended by the parties hereto to be a sample, which shall be modified
        by the mutual agreement of the parties hereto, from time to time]

                                                                   [Date]
[LESSEE]

Attention Mr.__________________

         This Site Lease is issued by MATC Celular, S. de R.L. de C.V. ("MATC
Celular") under terms of that certain Amended and Restated Master Lease
Agreement (the "Master Lease Agreement") dated May 16, 2002, entered into by and
between MATC Celular and Grupo Iusacell Celular, S.A. de C.V. ("Lessee").

         Terms not otherwise defined herein shall have the meaning assigned to
them in the Master Lease Agreement or the Amended and Restated Build to Suit
Agreement, of even date, entered into by and between MATC Celular and Lessee.

         [IF APPLICABLE: A COPY OF THE PRIME LEASE RELATING TO THE MATC SITE
COVERED BY THIS SITE LEASE IS ATTACHED TO THIS EXHIBIT B-2 AS ATTACHMENT A.]

TOWER INFORMATION:

         Tower Name:             ______________             Coordinates: ______
         Tower Number:           ______________
         City, State and Region: ______________________________________________
         This Site is a MATC Existing Site

RENT AND TERM:

                  Commencement Date: ____________________

                  Rent: $ ________________________, payable monthly in
                  accordance with the terms of the Master Lease Agreement,
                  except for the first Rent payment which will be payable within
                  twenty (20) Business Days following the Commencement Date.

                  Refer to Section 4 of the Master Lease for the duration of the
                  Term (including renewal periods) and Section 5(b) of the
                  Master Lease for the annual escalation of the Rent.

LOCATION/IDENTIFICATION OF PREMISES

<PAGE>

                  Height of Center of Radiation (center point of 20 foot expanse
                  comprising the "Premises"):_______________________

LESSEE'S IMPROVEMENTS AND EQUIPMENT INFORMATION:

         Call Sign:      ______________         RX Frequency: ___________
         Antenna Height: ______________         Antenna Type: ___________
         TX Frequency:   ______________         Trans. Line: ____________

         THE SPACE TO BE LEASED FOR THE LOCATION OF LESSEE'S EQUIPMENT SHELTER
         IS DESCRIBED ON ATTACHMENT B ATTACHED TO THIS EXHIBIT B-2.

         LESSEE'S IMPROVEMENTS AND EQUIPMENT TO BE INSTALLED ON TOWER:

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------
                                      #1                #2                #3                    #4
-----------------------------------------------------------------------------------------------------------
<S>                                   <C>               <C>               <C>                   <C>
QUANTITY:
-----------------------------------------------------------------------------------------------------------
MANUFACTURER:
-----------------------------------------------------------------------------------------------------------
TYPE & MODEL #:
-----------------------------------------------------------------------------------------------------------
ANTENNA WEIGHT/LENGTH:
-----------------------------------------------------------------------------------------------------------
LINE TYPE:
-----------------------------------------------------------------------------------------------------------
LINE QUALITY & DIAMETER:
-----------------------------------------------------------------------------------------------------------
ANTENNA MOUNT HEIGHT
-----------------------------------------------------------------------------------------------------------
TOWER LEG:
-----------------------------------------------------------------------------------------------------------
DIRECTION OF RADIATION:
-----------------------------------------------------------------------------------------------------------
REQUESTED MOUNTING POSITION:
-----------------------------------------------------------------------------------------------------------
</TABLE>

         TRANSMISSION AND OTHER EQUIPMENT TO BE LOCATED IN LESSEE'S EQUIPMENT
         BUILDING:

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------------------------------
                                      #1                #2                #3                #4
-------------------------------------------------------------------------------------------------------
<S>                                   <C>               <C>               <C>               <C>
NUMBER OF CABINETS:
-------------------------------------------------------------------------------------------------------
# OF TRANSMITTERS PER
CABINET:
-------------------------------------------------------------------------------------------------------
MANUFACTURER:
-------------------------------------------------------------------------------------------------------
TYPE & MODEL #:
-------------------------------------------------------------------------------------------------------
TYPE OF SERVICE:
-------------------------------------------------------------------------------------------------------
RACK DIMENSIONS:
-------------------------------------------------------------------------------------------------------
RATED POWER:
-------------------------------------------------------------------------------------------------------
CALL SIGN:
-------------------------------------------------------------------------------------------------------
TX FREQUENCY:
-------------------------------------------------------------------------------------------------------
RX FREQUENCY:
-------------------------------------------------------------------------------------------------------
ELEC. SERVICE AMPS/VOLTS:
-------------------------------------------------------------------------------------------------------
NUMBER OF OUTLETS:
-------------------------------------------------------------------------------------------------------
POWER OUTLETS:
-------------------------------------------------------------------------------------------------------
ERP:
-------------------------------------------------------------------------------------------------------
DIMENSIONS (W" X D" X H")
-------------------------------------------------------------------------------------------------------
COMBINER/# OF PORTS:
-------------------------------------------------------------------------------------------------------
CABINET ALSO CONTAINS:
-------------------------------------------------------------------------------------------------------
GROUND SPACE DIMENSION (IF
APPL):
-------------------------------------------------------------------------------------------------------
</TABLE>

                                       -2-

<PAGE>

         [INFORMATION SIMILAR TO THAT PROVIDED ABOVE SHALL BE PROVIDED FOR ALL
         MICROWAVE AND PAGING EQUIPMENT INSTALLED ON THE SITE, AS APPLICABLE]

SITE DRAWINGS/STRUCTURALS (IF ANY) ARE ATTACHED TO THIS EXHIBIT B-2 AS
ATTACHMENT C.

Disclosure of environmental conditions required pursuant to Section 19 of the
Master Lease:

________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

         Upon signature of this Site Lease, the Lessee agrees to be bound by the
provisions of the Master Lease. Any of the parties may cause this Site Lease and
the Master Lease to be registered at the Public Registry of Property of the
location of the Premises, as specified above.

________________________________                MATC Celular, S. de R.L. de C.V.

________________________________                ______________________________
By:                                             By:
Position:                                       Position:
Date:                                           Date:

Attachment A to Exhibit B-2:  Ground Lease
Attachment B to Exhibit B-2:  Space for Equipment Shelter
Attachment C to Exhibit B-2:  Site Drawings/Structurals

                                       -3-

<PAGE>

                                   EXHIBIT "C"

                               SPANISH TRANSLATION

<PAGE>

                                   EXHIBIT "D"

                                ACCESS PROCEDURES

[This is intended by the parties hereto to be a sample, which shall be modified
       by the mutual agreement of the parties hereto, from time to time]

1.       So long as the work to be performed at the MATC Site is ground-based
only, Lessee shall have the right to enter the MATC Site at anytime during the
Term, without notice to MATC Celular, in accordance with Section 7(f).

2.       Except for emergency situations, in the event that Lessee or any of its
employees, representatives, agents, contractors, or subcontractors enters the
MATC Site to perform any form of maintenance, repair, installation, or
inspection of any equipment located on the tower structure, Lessee must contact
MATC Celular no less than seven (7) days prior to such visit as follows:

         a.       Call and personally speak with the Director of Operations at
                  55-5-240-2000.

         b.       Fax a notification of the type of work to be performed, date
                  and time of intended visit to the Director of Operations at
                  fax number 55-5-240-2026.

3.       In the event of an emergency situation in which Lessee or any of its
employees, representatives, agents, contractors, or subcontractors needs to
enter the MATC Site to perform emergency repairs, to the extent possible, Lessee
shall attempt to contact the Director of Operations at 55-5-240-2000 by
telephone or shall leave a message for the Director of Operations prior to their
entrance to the MATC site and may enter such MATC Site if they have not had any
contact with the Director of Operations within two hours after leaving such
message. In the event that such contact or message is not possible, Lessee shall
personally speak with the Director of Operations as soon as practicable after
the emergency repairs have been made (but in no event more than twenty-four
hours).

                                       -2-

<PAGE>

                                   EXHIBIT "E"

                                 FORM OF JOINDER

                              JOINDER TO AGREEMENT

         This Joinder to that certain Amended & Restated Master Lease Agreement
dated May 16, 2002 by and between GRUPO IUSACELL CELULAR, S.A. DE C.V., for and
on behalf of itself and its Affiliates, and MATC CELULAR, S. DE R.L. DE C.V. ("
the Agreement") is executed by the undersigned, Grupo Iusacell, S.A. de C.V.,
and MATC Celular, S. de R.L. de C.V. in accordance with the provisions of
Section 2.01(b) of the Agreement. The undersigned hereby joins in the execution
and delivery of the Agreement, makes the representations set forth in the
Agreement, and agrees that the undersigned shall be deemed to be a Lessee for
all purposes under the Agreement. The undersigned agrees to be bound by all
terms, covenants and conditions contained in the Agreement, as a Lessee as
defined therein, as if the undersigned were an original party to the Agreement.

Date:

                                                ________________________________
                                                By:
                                                Name:
                                                Title:

AGREED TO AND ACKNOWLEDGED BY:                  AGREED TO AND ACKNOWLEDGED BY:

GRUPO IUSACELL CELULAR, S.A. DE C.V.            MATC CELULAR, S. DE R.L. DE C.V.

________________________________                ________________________________
By:                                             By:
Name:                                           Name:
Title:                                          Title:

                                       -3-

<PAGE>

                                   EXHIBIT "F"

                               MICROWAVE FORMULAE

Solids
..75 X height on tower (ft) X diameter of the dish (ft) = Monthly Fee

Grids
..50 X height on tower (ft) X diameter of the dish (ft) = Monthly Fee

All such amounts will remain subject to the three percent (3%) annual increase
contained in Section 5(b) of this Master Lease

                                       -4-

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