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                                                                   EXHIBIT 10.13

                                                                       EXECUTION
                                                                     COUNTERPART

                                                      EDC LOAN NO. 880-CHIL-7078
                                                         IDB LOAN NO. 1227/0C-CH

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                  AMENDED AND RESTATED PERFORMANCE UNDERTAKING

                          Dated as of December 22, 1999

                                      among

                                SR TELECOM INC.,

                         EXPORT DEVELOPMENT CORPORATION

                                       and

                         INTER-AMERICAN DEVELOPMENT BANK

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                  AMENDED AND RESTATED PERFORMANCE UNDERTAKING (this
"Agreement"), dated as of December 22, 1999. among SR TELECOM INC., a
corporation duly organized and validly existing under the laws of Canada
("SRT"), EXPORT DEVELOPMENT CORPORATION, a corporation established by an Act of
the Parliament of Canada ("EDC"), and INTER-AMERICAN DEVELOPMENT BANK, an
international organization established by the Articles of Agreement among its
member countries ("IDB", together with EDC, the "Senior Lenders").

                                   WITNESSETH

                  WHEREAS, Comunicacion y Telefonia Rural S.A., a sociedad
anonima duly organized and validly existing under the laws of Chile and the
indirectly, wholly-owned Subsidiary of SRT (the "Borrower"), has undertaken to
design, construct, install and operate a rural telecommunications network in
nine primary zones of Chile (the "Project");

                  WHEREAS, in order to finance the development and construction
of the Project, the Borrower has requested that EDC and IDB separately make
loans to it in an aggregate principal amount not exceeding $50,000,000;

                  WHEREAS, in order to finance a portion of the Project, the
Borrower and EDC are parties to an Amended and Restated Loan Agreement dated as
of the date hereof (the "EDC Loan Agreement"), providing, subject to the terms
and conditions thereof, for a loan to be made by EDC to the Borrower in an
aggregate amount not exceeding $25,000,000;

                  WHEREAS, in order to finance a portion of the Project, the
Borrower and IDB are parties to a Loan Agreement dated as of the date hereof
(the "IDB Loan Agreement" together with the EDC Loan Agreement, the "Senior Loan
Agreements"), providing, subject to the terms and conditions thereof, for a loan
to be made by IDB to the Borrower in an aggregate amount not exceeding
$25,000,000;

                  WHEREAS, to induce the Senior Lenders to enter into their
respective Senior Loan Agreements and as a condition precedent under the Common
Agreement, SRT has, inter alia, entered into this Agreement with the Senior
Lenders to undertake certain obligations for the benefit of the Senior Lenders;

                  NOW, THEREFORE, in consideration of the premises and of the
execution of the Senior Loan Agreements and for the making of the loans
thereunder, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, SRT agrees with the Senior Lenders
as follows:

                                    SECTION 1

                         DEFINITIONS AND INTERPRETATION

                  Section 1.01 Definitions. Each capitalized term used herein
(including the preamble and recitals hereto) and not otherwise defined herein
shall have the meaning assigned

                             Performance Undertaking

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to that term in Appendix A to the Amended and Restated Direct Agreement dated as
of the date hereof (the "Direct Agreement") among SRT, the Borrower and the
Senior Lenders. For purposes of Section 2.01 (a), the following terms shall have
the following meanings:

                  "Installed Lines" means, collectively, (a) Public Telephone
Lines and (b) Private Telephone Lines for which the Borrower has collected from
the subscriber thereto a minimum deposit of 44,700 Chilean Pesos.

                  "Force Majeure Event" means any act, event or condition that
causes delay in or failure of performance of obligations under this Agreement,
to the extent that such act, event or condition (a) is beyond the reasonable
control of SRT or the Borrower, (b) is not the result of any acts, omissions or
delays of SRT or the Borrower (or any third Person over whom SRT or the Borrower
has control, including any subcontractor), (c) is not an act, event or
condition, the risks or consequences of which SRT or the Borrower has expressly
agreed to assume hereunder and (d) cannot be cured, remedied, avoided, offset,
negotiated or otherwise overcome by the prompt exercise of due diligence of SRT
or the Borrower (or any third Person over whom SRT or the Borrower has control,
including any subcontractor). Force Majeure Events shall include the following
(if the requirements described in clauses (a) through (d) of the above sentence
are satisfied): hurricane, fire, tornado, landslide, earthquakes, acts of a
public enemy, plague or other epidemics, war, insurrection, riot or civil
disturbance, strikes (but excluding strikes limited to the activities of the
Project), an unreasonable failure to obtain any necessary Governmental Approval
from any Governmental Body provided that proper and timely application was made
therefor, payment of all necessary fees and charges was made and diligent and
continuous pursuit of such authorization or approval has been made, all in light
of the schedule for Completion of Network Construction (as defined in Section
2.01(a)) and the effect of delays thereon. Notwithstanding the foregoing, Force
Majeure Events shall not include (i) weather conditions which could reasonably
be anticipated by experienced contractors in Chile, (ii) any site conditions or
event arising therefrom, (iii) the occurrence of any manpower or material
shortages or (iv) any delay or failure (direct or indirect) in obtaining
materials, or any other delay, default or failure (financial or otherwise) of a
subcontractor, vendor or supplier except if such delay, default or failure
results from any act, event or condition which would, with respect to such
subcontractor, supplier or vendor, as the case may be, constitute a Force
Majeure Event if this definition were applicable to such subcontractor, supplier
or vendor.

                  "Private Telephone Line" means any installed and in-service
telephone line with dial tone of the Borrower which is not a Public Telephone
Line.

                  "Public Telephone Line" means any installed and in-service
coin operated telephone line with dial tone of the Borrower.

                  Section 1.02 Interpretation. The rules of interpretation set
out in the Direct Agreement shall apply mutatis mutandis to this Agreement as if
set out in full herein.

                             Performance Undertaking

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                                    SECTION 2

                             PERFORMANCE UNDERTAKING

                  Section 2.01 Undertakings.

                  (a)      Completion. SRT hereby irrevocably and
unconditionally undertakes to cause the "Completion of Network Construction",
which, for the purposes hereof, means that:

                           (i)      the Borrower shall have at least 22,500
                  Installed Lines, of which (A) 19,500 must be Private Telephone
                  Lines and (B) 3,000 must be Public Telephone Lines, in each
                  case, by December 31, 2000, which date may be extended with
                  the written consent of the Senior Lenders if a Force Majeure
                  Event has occurred in the sole determination of the Senior
                  Lenders;

                           (ii)     the Borrower shall be in full compliance
                  with the terms and conditions, including, without limitation,
                  the timing requirements, of each of the Concessions,
                  (including, without limitation, as such Concessions have been
                  modified by Acta de Notificacion No. 31,208-98 dated September
                  29, 1998 given and signed by the Minister of Transport and
                  Telecommunications for Chile);

                           (iii)    all the insurance policies required by
                  Section 8.04 of the Common Agreement are in place and
                  effective;

                           (iv)     all Governmental Approvals required for the
                  operation of the Project have been obtained and remain fully
                  effective;

                           (v)      the Independent Engineer shall have provided
                  a certificate substantially in the form of Exhibit A; and

                           (vi)     the Borrower shall certify to the Senior
                  Lenders that all aspects of the EHSM Plan have been fully
                  implemented.

                  (b)      Assistance. In addition to any other assistance
(monetary or otherwise) which SRT is obliged to provide to the Borrower pursuant
to the terms of the Transaction Documents (including, without limitation, the
provision of any necessary funding pursuant to the Project Funds Agreement), in
order to satisfy the undertaking set forth in Section 2.01 (a), SRT agrees:

                           (i)      to provide to the Borrower certain of its
                  employees to perform necessary tasks;

                           (ii)     to provide to the Borrower any necessary
                  advice and managerial, technical, engineering, accounting and
                  operational systems and assistance;

                           (iii)    to sell or otherwise make available to the
                  Borrower sufficient equipment, including without limitation,
                  SR500 microwave transmission systems and wireless local loop
                  equipment;

                             Performance Undertaking

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                           (iv)     to pay to the Borrower (which the Borrower
                  shall pay to SUBTEL) any fines, penalties or other levies
                  imposed on the Borrower by SUBTEL to the extent that the
                  Borrower has insufficient funds to pay any such fines,
                  penalties or other levies, (A) for delays or non-completion in
                  the Completion of Network Construction and for failure to
                  operate the Project in compliance with the Concessions and (B)
                  pursuant to terms and in amounts that mirror the fines,
                  penalties or other levies for the breaches noted in clause (A)
                  to be paid by the Borrower to SUBTEL under each of the
                  Concessions;

                           (v)      to ensure that no Concession is terminated
                  prior to the stated term thereof due to a failure of the
                  Borrower to comply with the Borrower's obligations under such
                  Concession; and

                           (vi)     to take any other action necessary.

                  Section 2.02 Waiver of Acceptance. SRT expressly waives notice
of acceptance of this Agreement and notice of any liability to which it may
apply. SRT also expressly waives any requirement that the Senior Lenders exhaust
any right, power or remedy, or proceed, against the Borrower under any
Transaction Document or any other agreement or instrument referred to therein,
or against any other Person under any other guarantee or security of the Senior
Lenders.

                  Section 2.03 Unconditional Undertakings. SRT's obligations
under this Agreement are absolute, unconditional and irrevocable and shall
remain in full force and effect without regard to, and SRT's obligations herein
will not be affected by:

                           (a) any actual or asserted lack of value,
         genuineness, validity, regularity or enforceability of the obligations
         of the Borrower under any of the Transaction Documents or any other
         agreement or instrument referred to herein or therein;

                           (b) any amendment of this Agreement or any of the
         other Transaction Documents, or waiver of, or consent to or departure
         from, any provision of this Agreement or any of the other Transaction
         Documents;

                           (c) the occurrence of any event or circumstance
         (including Borrower default) which could excuse SRT from performing its
         obligations under the Technical Services Agreement; or

                           (d) any breach, failure to perform or other action or
         inaction by either the Borrower or SRT under any of the Transaction
         Documents to which it is a party, or any breach, failure to perform or
         other action or inaction by any Governmental Body or by SUBTEL pursuant
         to the Concessions.

                             Performance Undertaking

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                                    SECTION 3

                         REPRESENTATION AND WARRANTIES

                  SRT confirms the representations and warranties contained in
Section 4 of the Direct Agreement, which representations and warranties are
incorporated herein by reference as if fully set forth in this Agreement.

                                    SECTION 4

                                 MISCELLANEOUS

                  Section 4.01. Termination. This Agreement shall terminate on
the earlier of (a) the date on which Completion of Network Construction has
occurred to the satisfaction of the Senior Lenders; and (b) the date on which
(i) all of the Commitments have been reduced to zero or have expired and (ii)
all of the Borrower's obligations under the Senior Loan Agreements are
indefeasibly paid in full. Upon the termination of this Agreement, the
obligations of the parties hereto shall terminate.

                  Section 4.02. Severability. If any provision of this Agreement
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby. If any provisions of this Agreement shall be invalid, illegal
or unenforceable in any jurisdiction, the validity, legality and enforceability
of such provision shall not in any way be affected or impaired in any other
jurisdiction thereby.

                  Section 4.03. Notices. Any notice, claim, request, demand,
consent designation, direction, instruction, certificate, report or other
communication to be given hereunder shall be given in writing in the English
language (or accompanied by an accurate English language translation upon which
the recipient shall have the right to rely for all purposes) and will be deemed
duly given when (a) personally delivered, (b) sent by facsimile transmission
(but only if, immediately after the transmission, the sender's facsimile machine
records in writing the correct answerback) or (c) ten days have elapsed after
mailing by certified or registered mail, postage prepaid, in each case addressed
to a party at its address or facsimile transmission number as set forth below or
to another address or facsimile number of which that party has given notice.
Notice of address or facsimile number change shall be effective only upon
receipt.

                  If to SRT:

                  8150 Trans Canada Highway
                  St. Laurent, Quebec, H4S 1M5
                  Attention: President & CEO
                  Telecopier: 514-335-2035

                             Performance Undertaking

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                  If to EDC:

                  151 O'Connor Street
                  Ottawa, Ontario
                  Canada, KlA 1K3
                  Attention: Loans Operations
                  Telecopier: 613-598-2514

                  If to IDB:

                  Private Sector Department
                  Inter-American Development Bank
                  1300 New York Avenue, N.W.
                  Washington, DC 20577
                  Attention:  Loan Administration Unit
                  Telecopier: 202-623-3639

                  Section 4.03 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED
BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

                  Section 4.04 Jurisdiction, Service of Process and Venue. The
provisions of Section 9(i), (j), (k) and (l) of the Direct Agreement are
incorporated herein by reference as if fully set forth in this Section 4.04.

                  Section 4.05 WAIVER OF JURY TRIAL. EACH PARTY HERETO
IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND
ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO
THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

                  Section 4.06 Amendments. This Agreement may be amended only by
an agreement in writing executed by each of the parties hereto.

                  Section 4.07 Expenses. SRT shall be liable for all
out-of-pocket expenses of the Senior Lenders (including the reasonable fees and
expenses of counsel for the Senior Lenders) incurred in connection with the
enforcement of this Agreement.

                  Section 4.08 Benefit of Agreement. Nothing in this Agreement,
express or implied, shall give to any Person, other than the parties hereto and
their successors and permitted assigns hereunder and under any Transaction
Document, any benefit or any legal or equitable right or remedy under this
Agreement.

                  Section 4.09 Remedies. No remedy herein conferred upon the
Senior Lender is intended to be exclusive of any other remedy and each and every
such other remedy shall be cumulative and shall be in addition to every other
remedy given hereunder or now or hereafter existing at law or in equity or by
statute or otherwise.

                             Performance Undertaking

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                  Section 4.10 Effectiveness. This Agreement shall come into
full force and effect, and amend and restate, the Performance Undertaking dated
as of April 13, 1999 between SRT and EDC as of the date on which the EDC Loan
Agreement becomes effective in accordance with Section 6 thereof.

                  Section 4.11 Counterparts. This Agreement may be executed in
two or more counterparts, each of which shall be deemed to be an original but
all of which together shall constitute one and the same instrument.

                  Section 4.12 Headings. The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect any of the
terms hereof.

                  Section 4.13 No Waiver. No failure on the part of the Senior
Lenders to exercise, and no course of dealing with respect to, and no delay in
exercising, any right, power or remedy hereunder shall operate as a waiver
thereof; nor shall any single or partial exercise by the Senior Lenders of any
right, power or remedy hereunder preclude any other or further exercise thereof
or the exercise of any other right, power or remedy.

                  Section 4.14. Successors and Assigns. This Agreement shall be
binding upon and enure to the benefit of the parties hereto and their respective
successors and assigns. SRT shall not assign or transfer any of its rights or
obligations hereunder.

                             Performance Undertaking

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                  IN WITNESS WHEREOF, the parties hereto, by their officers duly
authorized, have caused this Performance Undertaking to be duly executed and
delivered as of the date first above written.

                                       SR TELECOM INC.

                                       By: /s/ W. Ronald Couchman
                                           ------------------------------
                                           Name:  W. Ronald Couchman
                                           Title: Chief Executive Officer

                                       By: /s/ David L. Adams
                                           -----------------------------
                                           Name:  David L. Adams
                                           Title: Chief Financial officer

                            Performance Undertaking

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                                       EXPORT DEVELOPMENT CORPORATION

                                       By: /s/ Bruce Dunlop
                                           -------------------------------
                                           Name:  Bruce Dunlop
                                           Title: Financial Services Manager

                                       BY: /s/ Brian Craig
                                           -------------------------------
                                           Name:  Brian Craig
                                           TITLE: Financial Services Manager

                            Performance Undertaking

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                                       INTER-AMERICAN DEVELOPMENT BANK

                                       By: /s/ Bernardo Frydman
                                           -------------------------------
                                           Name: Bernardo Frydman
                                           Title: Deputy Manager, Private Sector
                                           Department

                            Performance Undertaking