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                                                                  Exhibit 10.5

                                                                  EXECUTION COPY






                         RIGHT OF NEGOTIATION AGREEMENT

                                     BETWEEN

                         METROMEDIA FIBER NETWORK, INC.,

                                       AND

                            VERIZON INVESTMENTS INC.



                           DATED AS OF OCTOBER 1, 2001

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                                TABLE OF CONTENTS

                                                                            PAGE

ARTICLE I   DEFINITIONS 1

            Section 1.1  Certain Definitions ................................  1

ARTICLE II  RIGHT OF NEGOTIATION ............................................  5

            Section 2.1  Right of Negotiation ...............................  5

ARTICLE III  REPRESENTATIONS AND WARRANTIES .................................  6

            Section 3.1  Representations and Warranties of the Company ......  6

            Section 3.2  Representations and Warranties of Verizon ..........  7

ARTICLE IV  MISCELLANEOUS ...................................................  8

            Section 4.1  Specific Performance ...............................  8

            Section 4.2  Entire Agreement ...................................  8

            Section 4.3  Amendment ..........................................  8

            Section 4.4  Term ...............................................  8

            Section 4.5  Severability .......................................  9

            Section 4.6  Notices ............................................  9

            Section 4.7  Governing Law ...................................... 10

            Section 4.8  Successors and Assigns ............................. 10

            Section 4.9  Interpretation ..................................... 10

            Section 4.10 Counterparts ....................................... 10


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                                                                  EXECUTION COPY

                         RIGHT OF NEGOTIATION AGREEMENT

       RIGHT OF NEGOTIATION AGREEMENT, dated as of October 1, 2001 (this
"AGREEMENT"), by and among Metromedia Fiber Network, Inc., a Delaware
corporation (the "COMPANY"), and Verizon Investments Inc., a Delaware
corporation ("VERIZON").

                              W I T N E S S E T H:

       WHEREAS, the Company and Verizon are parties to the Note Purchase
Agreement, of even date herewith (the "PURCHASE AGREEMENT"), pursuant to which,
among other things, Verizon has agreed to purchase from the Company $50,000,000
in principal amount of the Company's 8.5% Senior Secured Convertible Notes due
2011; and

       WHEREAS, each of the parties hereto acknowledges and agrees that, as a
condition to Verizon's willingness to enter into the Purchase Agreement and to
consummate the transactions contemplated thereby, Verizon has required, among
other things, that the Company enter into, and the Company has agreed to enter
into, this Agreement;

       NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants and agreements contained herein, and intending to be legally bound
hereby, the parties hereto hereby agree as follows:

                                   ARTICLE I

                                   DEFINITIONS

       Section 1.1 Certain Definitions. As used in this Agreement:

       (a) The term "ACQUISITION TRANSACTION" shall mean any transaction or
series of transactions that would, if consummated, result in any of the
following: (i) any Person or Group, other than a Permitted Holder, becoming the
Beneficial Owner, directly or indirectly, of 35% or more of the Voting Stock
(measured by voting power rather than number of shares) (for the purposes of
this clause, such other Person shall be deemed to Beneficially Own any voting
stock of a specified corporation held by a parent corporation if such other
person beneficially owns, directly or indirectly, more than 35% of the voting
stock (measured by voting power rather than by number of shares) of such parent
corporation and the Permitted Holders beneficially own, directly or indirectly,
in the aggregate a lesser percentage of voting stock (measured by voting power
rather than by number of shares) of such parent corporation and do not have the
right or ability by voting power, contract or otherwise to elect or designate
for election a majority of the board of directors of such parent corporation),
(ii) the Company consolidating or merging with or into any other Person, or any
Person consolidating with, or merging with or into, the Company, other than a
consolidation or merger (a) of the Company into a wholly owned subsidiary of the
Company or (b) pursuant to a transaction in which the outstanding Voting Stock
is changed into or exchanged for cash, securities or other

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property with the effect that the beneficial owners of the outstanding Voting
Stock immediately prior to such transaction, beneficially own, directly or
indirectly, at least a majority of the voting stock (measured by voting power
rather than number of shares) of the surviving corporation immediately following
such transaction, (iii) the Transfer (other than by way of merger or
consolidation), in one or a series of related transactions, of all or
substantially all of the assets of the Company and its Subsidiaries taken as a
whole to any Person other than a wholly owned subsidiary of the Company or a
Permitted Holder or a Person more than 50% of the voting stock (measured by
voting power rather than by number of shares) of which is owned, directly or
indirectly, following such transaction or transactions by the Permitted Holders,
including any such Transfer made in accordance with any applicable provision of
United States Code, 11 U.S.C. sections 101 ET SEQ. (or any successor statute
thereto); PROVIDED, HOWEVER, that Transfers in the ordinary course of business
of capacity on fiber optic or cable systems owned, controlled or operated by the
Company or any of its Subsidiaries or of telecommunications capacity or
transmission rights, rights of way or conduit acquired by the Company or any of
its Subsidiaries for use in the business of the Company or any of its
Subsidiaries, including, without limitation, for sale, lease, transfer,
conveyance or other disposition, in the ordinary course of business, to any
customer of the Company or any Subsidiaries shall not be deemed a disposition of
assets for purposes of this clause (iii), or (iv) the adoption of a plan
relating to the total liquidation of the Company.

       (b) The term "ACQUISITION PROPOSAL" shall have the meaning given to such
term in Section 2.1(a) hereof.

       (c) The term "ACQUISITION PROPOSAL NOTICE" shall have the meaning given
to such term in Section 2.1(a) hereof.

       (d) The term "AFFILIATE" shall have the meaning given to such term in
Rule 12b-2 under the Securities Exchange Act of 1934, as amended or any
successor act thereto, and the rules and regulations promulgated thereunder from
time to time.

       (e) The term "AGREEMENT" shall have the meaning given to such term in the
introductory paragraph hereof.

       (f) The terms "BENEFICIAL OWNERSHIP" and "BENEFICIAL OWNER" shall have
the meanings given such terms in Section 13(d)(3) of the Securities Exchange Act
of 1934, as amended or any successor act thereto, and the rules and regulations
promulgated thereunder.

       (g) The term "BUSINESS DAY" means any day other than a Legal Holiday.

       (h) The term "CLASS A COMMON STOCK" shall mean the Company's Class A
Common Stock, par value $.01 per share.

       (i) The term "CLASS B COMMON STOCK" shall mean the Company's Class B
Common Stock, par value $.01 per share.


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       (j) The term "COMPANY" shall mean Metromedia Fiber Network, Inc., a
Delaware corporation, and any successor thereto.

       (k) The term "GAAP" shall mean generally accepted accounting principles
in the United States of America as in effect from time to time.

       (l) The term "GOVERNMENTAL ENTITY" shall mean any nation or government,
any state, local or other political subdivision thereof, any court, arbitrator,
official, agency, department or other Person exercising executive, legislative,
judicial, regulatory or administrative functions of or pertaining to government,
or any federal, state or local governmental or regulatory agency, authority,
commission or instrumentality.

       (m) The term "GROUP" shall have the meaning given such term in Section
13(d)(3) of the Securities Exchange Act of 1934, as amended or any successor act
thereto, and the rules and regulations promulgated thereunder.

       (n) The term "LEGAL HOLIDAY" means a Saturday, a Sunday or a day on which
banking institutions in the City of New York or at a place of payment are
authorized by law, regulation or executive order to remain closed. If a payment
date is a Legal Holiday at a place of payment, payment may be made at that place
on the next succeeding day that is not a Legal Holiday, and no interest shall
accrue on such payment for the intervening period.

       (o) The term "NEGOTIATION PERIOD" shall have the meaning given to such
term in Section 2.1(b) hereof.

       (p) The term "PERMITTED HOLDER" shall mean Metromedia Company, its
general partners and their respective Related Persons and Persons that would
constitute a Class B Permitted Holder, each as defined in the Company's Amended
and Restated Certificate of Incorporation as in effect on the date hereof.

       (q) The term "PERSON" shall mean any individual, sole proprietorship,
partnership, limited liability company, joint venture, trust, unincorporated
organization, association, corporation, institution, public benefit corporation,
entity or government (whether foreign, federal, state, county, city, municipal
or otherwise, including any instrumentality, division, agency, body or
department thereof).

       (r) The term "SIGNIFICANT ASSET DISPOSITION" shall mean any Transfer, in
one or a series of related transactions by the Company or one of its
Subsidiaries to a Third Party of assets (other than cash) that have an aggregate
book value (as determined in accordance with GAAP) of at least $390 million,
including any such Transfer made in accordance with any applicable provision of
United States Code, 11 U.S.C. sections 101 ET SEQ. (or any successor statute
thereto), other than (x) a sale of all or substantially all of the assets of the
Company and its Subsidiaries (which shall be deemed an Acquisition Transaction
under clause (iii) of the definition of such term), or (y) any Transfer in the
ordinary course of business of capacity on fiber optic or cable systems owned,
controlled or operated by the Company or any of its Subsidiaries or of
telecommunications capacity


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or transmission rights, rights of way or conduit acquired by the Company or any
of its Subsidiaries for use in the business of the Company or any of its
Subsidiaries, including, without limitation, for sale, lease, transfer,
conveyance or other disposition, in the ordinary course of business, to any
customer of the Company or any of its Subsidiaries, shall not be deemed a
Significant Asset Disposition.

       (s) The term "SIGNIFICANT ASSET DISPOSITION PROPOSAL" shall have the
meaning given to such term in Section 2.1(a) hereof.

       (t) The term "SIGNIFICANT ASSET DISPOSITION PROPOSAL NOTICE" shall have
the meaning given to such term in Section 2.1(a) hereof.

       (u) The term "SUBSIDIARY" means (i) any corporation of which an aggregate
of 50% or more of the outstanding capital stock having ordinary voting power to
elect a majority of the board of directors of such corporation (irrespective of
whether, at the time, capital stock of any other class or classes of such
corporation shall have or might have voting power by reason of the happening of
any contingency) is at the time, directly or indirectly, owned legally or
beneficially by the Company and/or one or more Subsidiaries of the Company, and
(ii) any partnership, joint venture or other entity in which the Company and/or
one or more Subsidiaries of the Company shall have an interest (whether in the
form of voting or participation in profits or capital contributions) of 50% or
more.

       (v) The term "THIRD PARTY" shall mean any Person other than (i) Verizon
or any of its Affiliates or (ii) the Company .

       (w) The term "TRANSFER" (including, with correlative meaning,
"Transferred") shall mean any, direct or indirect, offer, sale, lease,
conveyance, transfer, assignment, exchange, grant of an option or right to
purchase, or other disposition of any kind.

       (x) The term "VERIZON PARTY" shall have the meaning given to such term in
Section 2.1(b) hereof.

       (y) The term "VOTING STOCK" shall mean (i) the Class A Common Stock, the
Class B Common Stock and any other securities issued by the Company having the
ordinary power to vote in the election of directors of the Company (other than
securities having such power only upon the happening of a contingency), and (ii)
the common stock and any other securities issued by any successor to the Company
pursuant to a merger, consolidation or reorganization having the ordinary power
to vote in the election of directors of such successor company (other than
securities having such power only upon the happening of a contingency).


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                                   ARTICLE II

                              RIGHT OF NEGOTIATION

       Section 2.1 RIGHT OF NEGOTIATION.

       (a) If the Company (or, in the case of clause (ii), any Subsidiary of the
Company) (i)(x) desires, proposes or determines, or is actively considering in
response to an oral offer or proposal, to effect an Acquisition Transaction, or
(y) receives a bona fide written offer from a Third Party (determined in good
faith by the Company) with respect to an Acquisition Transaction (in any case
under clause (i)(x) or (i)(y), an "ACQUISITION PROPOSAL"), or (ii)(x) desires,
proposes or determines, or is actively considering in response to an oral offer
or proposal, to effect a Significant Asset Disposition, or (y) receives a bona
fide written offer from a Third Party (determined in good faith by the Company
or the relevant Subsidiary) with respect to a Significant Asset Disposition (in
any case under clause (ii)(x) or (ii)(y), a "SIGNIFICANT ASSET DISPOSITION
PROPOSAL"), then the Company shall promptly provide written notice to Verizon of
such Acquisition Proposal or of such Significant Asset Disposition Proposal (to
the extent such notice pertains to an Acquisition Proposal, the "ACQUISITION
PROPOSAL NOTICE"; and to the extent such notice pertains to a Significant Asset
Disposition Proposal, the "SIGNIFICANT ASSET DISPOSITION PROPOSAL NOTICE"). Any
Significant Asset Disposition Proposal Notice shall include a complete and
accurate description of the material terms and conditions of the Significant
Asset Disposition Proposal, including, without limitation, a description of the
assets contemplated to be Transferred in the proposed Significant Asset
Disposition.

       (b) Assuming Verizon (or its designee referred to below) enters into a
customary confidentiality agreement, for a period of ten (10) Business Days
following the receipt by Verizon of an Acquisition Proposal Notice or a
Significant Asset Disposition Proposal Notice (the "NEGOTIATION PERIOD"),
Verizon or its designee (which designee shall be an Affiliate of Verizon that
is, directly or indirectly, 100% owned by Verizon Communications Inc. or is
otherwise acceptable to the Company) (the "VERIZON PARTY"), shall have the
nonexclusive right to negotiate with the Company, and to conduct reasonable and
customary due diligence, in connection with the proposed Acquisition Transaction
or the proposed Significant Asset Disposition, as the case may be. If, during
the Negotiation Period, the Verizon Party offers or otherwise proposes to
effect, or seeks to negotiate with the Company with respect to, an Acquisition
Transaction or a Significant Asset Disposition (with respect to the same assets
subject to the Significant Asset Disposition Proposal), as the case may be, then
the Company shall negotiate with the Verizon Party, and cooperate with its due
diligence inquiries, in good faith during the remainder of the Negotiation
Period; PROVIDED, HOWEVER, that the Company shall not be under any obligation to
accept any such offer or other proposal made by the Verizon Party to effect an
Acquisition Transaction or a Significant Asset Disposition or to accept any
other offer.

       (c) During the Negotiation Period, the Company shall not (and shall cause
its Subsidiaries not to), directly or indirectly, enter into any exclusivity
agreement or any definitive agreement (other than a customary confidentiality
agreement) with any


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Third Party with respect to or otherwise relating to the subject Acquisition
Proposal or Significant Asset Disposition Proposal, as the case may be.

       (d) If the Company and the Verizon Entity have not entered into an
exclusivity agreement or a definitive agreement with respect to or otherwise
relating to the subject Acquisition Transaction or Significant Asset
Disposition, as the case may be, then the Company shall have a period of 90
calendar days following the expiration of the Negotiation Period to enter into
an exclusivity agreement or definitive agreement with a Third Party with respect
to or otherwise relating to the subject Acquisition Proposal or Significant
Asset Disposition Proposal, as the case may be (it being understood that the
Company shall not be obligated to enter into any such agreement); PROVIDED,
HOWEVER, that if any such exclusivity or definitive agreement is not so entered
into with a Third Party within such 90-day period, the provisions of Section
2.1(a) shall again be applicable with respect to the subject Acquisition
Proposal or Significant Asset Disposition Proposal, as the case may be; and
PROVIDED FURTHER, HOWEVER, that, if the Company enters into an exclusivity
agreement or definitive agreement with a Third Party with respect to or
otherwise relating to the subject Acquisition Proposal or Significant Asset
Disposition Proposal during such 90-day period and the Acquisition Transaction
or the Significant Asset Disposition contemplated by such agreement is not
consummated and such agreement is terminated, the provisions of Section 2.1(a)
shall again be applicable with respect to the subject Acquisition Proposal or
Significant Asset Disposition Proposal, except if such exclusivity or definitive
agreement is terminated by the Company to accept an alternative proposal as
permitted by such exclusivity or definitive agreement or applicable Delaware
law.

       (e) In the event there exists several Significant Asset Disposition
Proposals with respect to different Significant Asset Dispositions, the terms of
this Section 2.1 shall apply to each Significant Asset Disposition Proposal
severally.

       (f) For clarification purposes, it is understood and agreed that, in the
event the Company enters into a definitive agreement with a Third Party with
respect to an Acquisition Transaction or a Significant Asset Disposition,
nothing in this Agreement shall prohibit or preclude Verizon or any of its
Affiliates from making a proposal regarding the consummation of a competing or
alternative Acquisition Transaction or Significant Asset Disposition, as the
case may be.

                                  ARTICLE III

                         REPRESENTATIONS AND WARRANTIES

       Section 3.1 REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company
represents and warrants to Verizon as follows:

       (a) AUTHORITY TO EXECUTE AND PERFORM AGREEMENTS. The Company has the full
legal capacity, right and power and all authority required to enter into,
execute and deliver this Agreement and to perform and comply fully with its
obligations hereunder. The execution and delivery of this Agreement by the
Company have been


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duly authorized by all requisite organizational action on the part of the
Company. This Agreement has been duly executed and delivered by, and constitutes
the legal, valid and binding obligation of, the Company enforceable against the
Company in accordance with its terms, except (A) as the enforceability may be
limited by bankruptcy, insolvency, reorganization, fraudulent conveyance,
moratorium or similar laws now or hereafter in effect generally affecting
creditors' rights or by general principles of equity, regardless of whether such
enforceability is considered in a proceeding in equity or at law, and (B) the
remedy of specific performance and injunctive relief hereunder may be subject to
equitable defenses and to the discretion of the court before which any
proceeding therefor may be brought.

       (b) NO CONFLICTS; CONSENTS.

              (i) The execution and delivery by the Company of this Agreement do
       not, and the consummation of the transactions contemplated hereby and the
       compliance with the provisions hereof applicable to it will not, conflict
       with or result in any violation of or default (with or without notice or
       lapse of time, or both) under (A) any contract, agreement or other
       binding arrangement to which the Company is a party, (B) any charter,
       by-laws, trust agreement, partnership agreement or any other
       organizational document of the Company, if applicable, or (C) any law,
       statute, rule or regulation, or any judgment, order, writ, injunction or
       decree of any Governmental Entity applicable to the Company.

              (ii) Other than filing this Agreement or a Form 8-K, under the
       Securities Exchange Act of 1934, as amended, no consents, approvals or
       authorizations of, or notices or filings with, any Person or Governmental
       Entity are required to be obtained or made by the Company in connection
       with the execution and delivery by the Company of this Agreement, and the
       consummation of the transactions contemplated hereby and the compliance
       with the provisions hereof applicable to the Company.

       Section 3.2 REPRESENTATIONS AND WARRANTIES OF VERIZON. Verizon represents
and warrants to the Company as follows:

       (a) AUTHORITY TO EXECUTE AND PERFORM AGREEMENTS. Verizon has the full
legal right and power and all authority required to enter into, execute and
deliver this Agreement and to perform and comply fully with Verizon's
obligations hereunder. The execution and delivery of this Agreement by Verizon
have been duly authorized by all requisite corporate action on the part of
Verizon. This Agreement has been duly executed and delivered by, and constitutes
the legal, valid and binding obligation of, Verizon enforceable against Verizon
in accordance with its terms, except (A) as the enforceability may be limited by
bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or
similar laws now or hereafter in effect generally affecting creditors' rights or
by general principles of equity, regardless of whether such enforceability is
considered in a proceeding in equity or at law, and (B) the remedy of specific
performance and injunctive relief hereunder may be subject to equitable defenses
and to the discretion of the court before which any proceeding therefor may be
brought.


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       (b) NO CONFLICTS; CONSENTS.

              (i) The execution and delivery by Verizon of this Agreement do
       not, and the consummation of the transactions contemplated hereby and the
       compliance with the provisions hereof applicable to it will not, conflict
       with or result in any violation of or default (with or without notice or
       lapse of time, or both) under (A) any contract, agreement or other
       binding arrangement to which Verizon is a party, (B) Verizon's
       certificate of incorporation or by-laws, or (C) any law, statute, rule or
       regulation, or judgment, order, writ, injunction or decree of any
       Governmental Entity applicable to Verizon.

              (ii) No consents, approvals or authorizations of, or notices or
       filings with, any Person or Governmental Entity are required to be
       obtained or made by Verizon in connection with the execution and delivery
       by Verizon of this Agreement, and the consummation of the transactions
       contemplated hereby and the compliance with the provisions hereof
       applicable to Verizon.

                                   ARTICLE IV

                                  MISCELLANEOUS

       Section 4.1 SPECIFIC PERFORMANCE. The parties hereto agree and declare
that legal remedies may be inadequate to enforce the provisions of this
Agreement and, therefore, the parties shall be entitled to specific performance
of the terms hereof, in addition to any other remedy at law or in equity. It is
accordingly agreed that the parties shall be entitled to an injunction or
injunctions to prevent or cure breaches of the provisions of this Agreement and
to enforce specifically the terms and provisions of this Agreement.

       Section 4.2 ENTIRE AGREEMENT. This Agreement and other agreements
expressly referred to herein constitute the entire agreement among the Company
and Verizon with respect to the express subject matter hereof and supersedes all
prior agreements and understandings, both written and oral, among the Company
and Verizon with respect to the express subject matter hereof.

       Section 4.3 AMENDMENT. This Agreement may not be amended except by an
instrument in writing signed by the Company and Verizon

       Section 4.4 TERM. This Agreement shall terminate on the earliest to occur
of: (i) the consummation of an Acquisition Transaction; (ii) the 90th
consecutive day on which Verizon or one of its Affiliates does not Beneficially
Own shares of Class A Common Stock equal to 2% or more of the aggregate number
of issued and outstanding shares of Class A Common Stock and Class B Common
Stock as of the date hereof; IT BEING UNDERSTOOD that the term "Beneficially
Own" for the purposes of this clause (ii) shall presume that any securities held
by Verizon or its Affiliates that are convertible into shares of Class A Common
Stock are immediately convertible into shares of Class A Common Stock,
notwithstanding any term in any such securities to the


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contrary; or (iii) the tenth anniversary of the date hereof.

       Section 4.5 SEVERABILITY. If any term or other provision of this
Agreement is invalid, illegal or incapable of being enforced by any rule or law,
or public policy, all other conditions and provisions of this Agreement shall
nevertheless remain in full force and effect so long as the economic or legal
substance of this Agreement is not affected in any manner materially adverse to
any party. Upon such determination that any term or other provision is invalid,
illegal or incapable of being enforced, the parties hereby shall negotiate in
good faith to modify this Agreement so as to effect the original intent of the
parties as closely as possible to the fullest extent permitted by applicable law
in a mutually acceptable manner in order that the terms of this Agreement remain
as originally contemplated.

       Section 4.6 NOTICES. All notices and other communications given or made
pursuant hereto shall be in writing and shall be deemed to have been duly given
or made and shall be effective (a) upon receipt if delivered personally, (b)
upon receipt of a transmission confirmation if sent by facsimile (with a
confirming copy sent by overnight courier), and (c) on the next business day if
sent by Federal Express, United Parcel Service, Express Mail or other reputable
overnight courier to the parties at the following addresses (or at such other
address for a party as shall be specified by notice):

                  If to the Company:

                  David A. Persing, Esq.
                  Metromedia Fiber Network, Inc.
                  c/o Metromedia Company
                  One Meadowlands Plaza
                  East Rutherford, New Jersey  07073-2137
                  Telecopy Number:  (201) 531-2803

                  with a copy to:

                  Paul, Weiss, Rifkind, Wharton & Garrison
                  1285 Avenue of the Americas
                  New York, New York  10019-6064
                  Attn:  Douglas A. Cifu, Esq.
                  Telecopy Number:  (212) 757-3990

                  If to Verizon:

                  Verizon Investments Inc.
                  3900 Washington Street, 2nd Floor
                  Wilmington, DE 19802
                  Attn:  President
                  Telecopy Number:  (302) 761-4228


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                  with copies to:

                  Verizon Communications Inc.
                  1095 Avenue of the Americas
                  New York, New York  10036
                  Attn:  Associate General Counsel - Strategic Transactions
                  Telecopy Number:  (212) 764-2739

                  and

                  Weil, Gotshal & Manges LLP
                  767 Fifth Avenue
                  New York, New York  10153
                  Attn:  Frederick S. Green, Esq.
                  Telecopy Number:  (212) 310-8007


       Section 4.7 GOVERNING LAW. This Agreement shall be governed by and
construed in accordance with, the applicable laws of the State of Delaware,
without giving effect to any choice of law or conflict of law provisions.

       Section 4.8 SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon
and inure to the benefit of the parties and their successors and legal
representatives. Neither party to this Agreement shall be permitted to assign
this Agreement; PROVIDED, that, Verizon may assign its rights under this
Agreement to any Affiliate that agrees in writing to be bound by the terms of
this Agreement.

       Section 4.9 INTERPRETATION. For the purposes of this Agreement, (i) terms
defined in the singular shall be held to include the plural and VICE VERSA and
words of one gender shall be held to include the other gender as the context
requires, and (ii) the terms "hereof", "herein", "hereunder" and "herewith" and
words of similar import shall, unless otherwise stated, be construed to refer to
this Agreement as a whole (including the schedules hereto) and not to any
particular provision of this Agreement. Where a word or phrase is defined
herein, each of its other grammatical forms shall have a corresponding meaning.

       Section 4.10 COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be an original and all of which, when taken
together, shall constitute one and the same instrument.

                     [Signatures appear on following page.]


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       IN WITNESS WHEREOF, each of the parties hereto have caused this Agreement
to be duly executed on the date hereof.

                                       THE COMPANY:

                                       METROMEDIA FIBER NETWORK, INC.


                                       By: /s/ Nick Tanzi
                                           -------------------------------------
                                           Name:  Nick Tanzi
                                           Title: President and CEO



                                       VERIZON:

                                       VERIZON INVESTMENTS INC.


                                       By: /s/ Phil Seskin
                                           -------------------------------------
                                           Name:  Phil Seskin
                                           Title: Senior Vice-President