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                                                                 EXHIBIT 4.25


                  AMENDED AND RESTATED CO-DEVELOPMENT AGREEMENT

THIS AMENDED AND RESTATED CO-DEVELOPMENT AGREEMENT Dated For Reference the 29th
day of September, 2000

BETWEEN:

                  360NETWORKS INC.

                  ("360")

AND:

                  360FIBER LTD.

                  ("360fiber")

AND:

                  360CAYER LTEE.

                  ("360Cayer")

AND:

                  WFI URBANLINK LTD.

                  ("Urbanlink")

WHEREAS:

A. 360fiber and 360Cayer (collectively "Fiber/Cayer"), 360 and Urbanlink have
entered into a Co-Development Agreement (the "Co-Development Agreement") to
record their respective rights and obligations relating to the co-development of
telecommunications facilities in Canada.

B. 360, Fiber/Cayer and Urbanlink wish to amend and restate the Co-Development
Agreement in its entirety by executing this Agreement.

IN CONSIDERATION of the mutual agreements in this Agreement and subject to the
terms and conditions specified in this Agreement, the parties agree as follows:


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                                   ARTICLE 1
                                   DEFINITIONS

1.1      DEFINITIONS

In this Agreement, including the recitals and the schedules, the following words
and expressions have the following meanings unless the context otherwise
requires:

"Affiliate" of any Person means any other Person that, directly or indirectly,
controls or is controlled by or is under common control with such Person, and
for the purposes of this definition "control" (including correlative meanings of
the terms "controlled by" and "under common control with") means the power to
direct or cause the direction of the management and policies of any Person,
whether through the ownership of shares or by contract or otherwise.

"Business Day" means a day on which Canadian chartered banks are open for the
transaction of business in Vancouver, British Columbia.

"Cable" means the fiber optic cable and the strands contained therein, and
associated splicing connections, splice boxes and bolts to be installed as part
of a Project.

"Class "A" Assets" shall have the meaning specified in Section 6.2.

"Class "B" Assets" shall have the meaning specified in Section 6.2.

"Fiber/Cayer" means 360Cayer for rights and obligations relating to that part of
any Project which is located in Quebec, and 360fiber for rights and obligations
relating to that part of any Project which is not located in Quebec, and either
or both of them, as the context may require, for sections of general
application.

"Force Majeure" means in relation to the performance of any obligation under
this Agreement any cause, condition or event of any nature whatsoever which is
not reasonably foreseeable at the time this Agreement is executed and which is
beyond the reasonable control of the party responsible for performance of such
obligation and not caused in whole or in part by its default, and which prevents
in whole or in part the performance by that party of its respective obligations
under this Agreement, and includes without limitation, acts of war, revolution,
riot, sabotage, vandalism, changes in governmental regulation, earthquakes,
storms, lightning, weather conditions that impede construction (including,
without limitation, the ground freezing before it would ordinarily do so) and
other Acts of God, local or national emergencies, rail accidents, strikes, third
party lockouts, work slowdowns and other labour disputes, delays in obtaining
approvals or inspections by third parties, any claim or other interference by
First Nations, delays in obtaining Underlying Rights, issues relating to
Underlying Rights that prevent or delay the performance of work by Fiber/Cayer
and decreased availability of track time from that expected by Fiber/Cayer.

"Initial Term" shall have the meaning specified in Section 3.4.

"Notice of Non-Acceptance" shall have the meaning specified in Section 5.4.


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"Notice of Completion" shall have the meaning specified in Section 5.4.

"Person" means an individual, partnership, corporation (including a business
trust), joint stock company, trust, unincorporated association, joint venture or
other entity or a foreign state or political subdivision thereof or any agency
of such state or subdivision.

"Projects" means all of the projects undertaken by the parties pursuant to this
Agreement for the development of telecommunications facilities in Canada and, in
respect of a particular Project, means all of the Cables, conduits and all
appurtenances thereto installed on the Underlying Rights relating thereto, and
"Project" means any of the Projects.

"Project Costs" means, with respect to a particular Project, all costs that are
incurred by 360fiber for the design, engineering, construction and installation
of such Project including, but not limited to, the Underlying Rights Costs.

"Project Specifications" means, with respect to a particular Project, the
engineering, design and operational specifications for the telecommunications
facilities that are to be developed as part of the Project, that are then
approved by 360, Fiber/Cayer and Urbanlink, acting reasonably and in good faith.

"Reasonable Efforts" shall mean efforts commercially and reasonably designed to
achieve the desired results, but shall not obligate a party to make unreimbursed
expenditures that are substantial in amount, in light of the circumstances to
which the requirement to use reasonable efforts applies.

"Segment" shall mean a longitudinal section of installed conduits.

"System" shall mean, with respect to a particular Project, the
telecommunications facility consisting of conduits, Cables and all appurtenances
thereto, developed or to be developed for such Project.

"Underlying Rights" means, with respect to a particular Project, all licenses,
leases, easements, rights-of-way, deeds, franchises, permits, authorizations,
consents and approvals (including, without limitation, any necessary local,
provincial, federal or First Nations authorizations and environmental permits)
and other rights, titles or interests as are necessary for the construction,
installation, operation, maintenance or repair of the System developed or to be
developed for such Project.

"Underlying Rights Costs" means, with respect to a particular Project, all
amounts expended by 360fiber to obtain the Underlying Rights and any renewals
thereof, including any charges for administrative costs incurred by 360fiber.

"Underlying Rights Requirements" means the terms, conditions, requirements,
restrictions, and/or limitations upon the parties' right to access, operate,
use, transfer or otherwise deal with the System imposed under the Underlying
Rights and the associated safety, operational and other rules and regulations
imposed in connection therewith or by applicable law.


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                                   ARTICLE 2
                                 CO-DEVELOPMENT

2.1      CO-DEVELOPMENT

Urbanlink agrees with 360 and Fiber/Cayer that Urbanlink shall provide to
Fiber/Cayer the first option to have any telecommunications facilities developed
by Urbanlink in Canada (including, without limitation, (x) the facilities known
as the City Builds and (y) the portion of the facilities on the terrestrial
build between Seattle and Vancouver, which portion is located in British
Columbia) developed as Projects under this Agreement.

                                   ARTICLE 3
                           OBLIGATIONS OF FIBER/CAYER

3.1      ENGINEERING AND CONSTRUCTION

Fiber/Cayer shall engineer, design, install and construct the Projects on behalf
of Urbanlink and 360, in compliance with the Project Specifications, applicable
laws and all applicable Underlying Rights Requirements. Fiber/Cayer shall supply
all vehicles, tools, equipment, labour and similar items and services necessary
for Fiber/Cayer to perform and complete the Project. Fiber/Cayer shall procure
all materials to be incorporated in and to become a permanent part of the system
or the project.

3.2      SYSTEM ROUTE

Urbanlink shall determine the specific route and location of the System for a
Project using advice from Fiber/Cayer on industry knowledge of dark fiber
demand; provided however that the route for such System will generally connect
to the locations agreed upon by Fiber/Cayer and Urbanlink for such project,
acting reasonably and in good faith.

3.3      CONTRACTORS

Fiber/Cayer may assign or subcontract to a third party any or all of the duties
or obligations of Fiber/Cayer under this Agreement, provided that Fiber/Cayer
shall remain obligated to Urbanlink under the terms of this agreement for any
such duties.

3.4      UNDERLYING RIGHTS

Fiber/Cayer shall obtain all Underlying Rights (other than municipal access
agreements, as provided in Section 4.2) that are reasonably necessary in order
to (i) permit Fiber/Cayer to construct, install, maintain and convey to
Urbanlink the system hereunder, (ii) permit Urbanlink and its successors to use,
own, operate, access and maintain the system as provided and permitted
hereunder, and (iii) permit Urbanlink to grant sublicenses or sub-easements, as
the case may be, to third parties, all in accordance with the terms and
conditions hereof and in accordance with the Underlying Rights Requirements.
Fiber/Cayer shall use Reasonable Efforts to require that the initial stated term
of any Underlying Rights shall be for a period that does not expire in
accordance with its ordinary terms within 25 years of its effective date, or
such other


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period as may then be agreed upon by Fiber/Cayer and Urbanlink, acting
reasonably and in good faith (the "Initial Term").

3.5      CHANGE REQUESTS

Fiber/Cayer or Urbanlink may request a change to the Project Specifications. The
other parties shall act reasonably and in good faith in considering any such
request.

3.6      INSPECTION BY URBANLINK

Urbanlink shall at all times the right to observe and inspect the performance by
Fiber/Cayer of the work to develop the Project.

3.7      ELECTRONICS

Urbanlink acknowledges that Fiber/Cayer is not supplying nor is Fiber/Cayer
obligated to supply to Urbanlink any optronics or electronics or optical or
electrical equipment of other similar facilities, all of which are the sole
responsibility of Urbanlink.

3.8      AS-BUILT DRAWINGS

As soon as reasonably practicable after the completion of a Project, Fiber/Cayer
shall provide to Urbanlink As-Built Drawings for the Project.

3.9      NO LIENS

At the time Fiber/Cayer transfers the ownership of and title to each Segment of
the Project to Urbanlink, the System shall be free and clear of all liens,
mortgages, security interests and encumbrances that may arise from any act or
omission of Fiber/Cayer.

3.10     WARRANTIES

On the completion of a Project, Fiber/Cayer shall cause all warranties received
by Fiber/Cayer from material suppliers, equipment makers or contractors to be
assigned to Urbanlink to the extent of Urbanlink's interest in the Project,
wherever practicable, and shall furnish to Urbanlink written evidence of such
assignment, or otherwise assist Urbanlink in enforcing same. Where such
assignment is impracticable or affects the retained interest of Fiber/Cayer in
the Project, Fiber/Cayer shall then hold such warranties in trust for the
benefit of Urbanlink and all other interested persons.

3.11     LIMITED WARRANTY

For a period of 12 months following the acceptance of the System for a Project,
Fiber/Cayer warrants that the engineering, design, construction and installation
of the System will be in compliance with the Project Specifications. Upon the
termination of the 12 month warranty, Urbanlink shall have no further recourse
against Fiber/Cayer or 360 with respect to the engineering, design, construction
and installation of the System, except for any claims made during such warranty
period, for which Fiber/Cayer shall remain responsible.


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3.12     CERTAIN WARRANTIES EXCLUDED

EXCEPT AS SET FORTH IN SECTION 3.11, OR AS MAY OTHERWISE BE SET FORTH
SPECIFICALLY AND EXPRESSLY ELSEWHERE IN THIS AGREEMENT, FIBER/CAYER AND 360 MAKE
NO WARRANTY OR CONDITION, EXPRESSED OR IMPLIED, WITH RESPECT TO THE SYSTEM OR
ANY SERVICES PROVIDED TO URBANLINK PURSUANT HERETO, INCLUDING ANY WARRANTY OR
CONDITION OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE, AND ALL
SUCH WARRANTIES ARE HEREBY EXPRESSLY DISCLAIMED. THE WARRANTIES SET FORTH IN
THIS AGREEMENT CONSTITUTE THE ONLY WARRANTIES MADE BY FIBER/CAYER OR 360 TO
URBANLINK WITH RESPECT TO THIS AGREEMENT AND ARE MADE IN LIEU OF ALL OTHER
WARRANTIES OR CONDITIONS, WRITTEN OR ORAL, STATUTORY, EXPRESSED OR IMPLIED.

                                   ARTICLE 4
                            OBLIGATIONS OF URBANLINK

4.1      COMPLIANCE WITH LAWS

Urbanlink shall be solely responsible for compliance with all legal and
regulatory requirements associated with its business or with ownership or
operation of the Systems including, without limitation, obtaining, maintaining
and paying for any and all regulatory permits, franchises, authorizations,
licences, consents or approvals that are required for Urbanlink's ownership, use
and operation of the Systems, and Fiber/Cayer shall have no responsibility or
liability whatsoever in connection therewith.

4.2      MUNICIPAL ACCESS AGREEMENTS

Without limiting the generality of Section 4.1, Urbanlink shall obtain, at its
own cost and expense, all municipal access agreements as may be required with
respect to the installation, construction or placement of the System by
Fiber/Cayer or with respect to Urbanlink's ownership, use and operation of the
System.

                                   ARTICLE 5
                          NORMAL RIGHTS AND OBLIGATIONS

5.1      PROJECT TEAM

Each of 360, Fiber/Cayer and Urbanlink shall designate employees to be members
of a project team for each Project, to facilitate and coordinate activities
under this Agreement. In addition, 360, Fiber/Cayer and Urbanlink shall
designate one or more individuals as onsite inspectors to monitor construction
progress. Fiber/Cayer shall convene periodic meetings of the project team to
review the progress of the work relating to a Project, such meetings to be held
at the principal office of Fiber/Cayer or at such other place as may be agreed
upon between the parties, acting reasonably and in good faith. The parties agree
that such meetings may be convened by means of a telephone conference or other
communications facility whereby all representatives participating in the meeting
can hear each other and communicate with each other.


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5.2      COMPLIANCE WITH UNDERLYING RIGHTS

Each of the parties covenants and agrees with the others to comply with and to
observe and perform their respective duties, obligations and responsibilities
under the Underlying Rights and under this Agreement. Throughout the term of
each of the Underlying Rights, each of the parties shall defend and protect
their collective rights and interests under the Underlying Rights and their
collective and individual rights to use the System as provided and permitted
hereunder against interfering or infringing rights, interests or claims of third
parties. The costs incurred in defending and protecting such rights and
interests shall be shared between Fiber/Cayer and Urbanlink in such proportions
as may then be agreed between them, acting reasonably and in good faith.

5.3      RISK OF LOSS

Fiber/Cayer shall bear all risks of loss to the System until title is
transferred, and Urbanlink shall bear all risks of loss to the System
thereafter.

5.4      COMPLETION AND ACCEPTANCE

The following acceptance procedures shall apply:

         (a)      Fiber/Cayer shall provide a written notice ("Notice of
                  Completion") to Urbanlink when Fiber/Cayer has completed the
                  System for a Project, including testing, and the System is
                  available for testing by Urbanlink. The Notice of Completion
                  shall include the test results obtained by Fiber/Cayer.

         (b)      Urbanlink shall have 14 days from the day Urbanlink receives
                  the Notice of Completion to determine whether the System is
                  constructed according the Project Specifications. Unless
                  Urbanlink gives notice in writing to Fiber/Cayer that the
                  System is not constructed according the Project
                  Specifications, clearly identifying the nature of the failure
                  by cross-reference to such Project Specifications (hereinafter
                  referred to as the "Notice of Non-Acceptance") within 14 days
                  of receiving the Notice of Completion as described above,
                  Urbanlink shall be deemed to have accepted the System.

         (c)      If Urbanlink gives a Notice of Non-Acceptance, Fiber/Cayer
                  shall have 30 days from the day Fiber/Cayer receives the
                  Notice of Non-Acceptance to remedy the defect and cause the
                  System to be constructed according to the Project
                  Specifications, or such longer period as may reasonably be
                  required for that purpose. The parties shall work together in
                  good faith to promptly identify those items that require
                  correction.

         (d)      Upon the expiration of the period referred to in Section
                  5.4(c), or upon notice from Fiber/Cayer that the conditions
                  identified in the Notice of Non-Acceptance had been corrected,
                  whichever occurs first, Urbanlink shall have an additional
                  seven day period to determine whether the System is
                  constructed according to the Project Specifications.


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         (e)      If Fiber/Cayer has failed to remedy the failure to meet the
                  Project Specifications identified in the Notice of
                  Non-Acceptance, and such failure remains unresolved at the end
                  of the 30 day period referred to in Section 5.4(c), the
                  parties shall have recourse to dispute resolution in
                  accordance with the terms of this Agreement.

5.5      FORCE MAJEURE

In no event shall Fiber/Cayer be liable to Urbanlink for any non-performance or
breach of contract, or for any costs, losses or damages including, without
limitation, loss of profit or consequential damages of any type whatsoever,
which arise by reason of or under conditions of Force Majeure. Fiber/Cayer shall
give notice to Urbanlink of any event of Force Majeure and shall use Reasonable
Efforts to remedy same or the causes thereof.

5.6      NO CONSEQUENTIAL DAMAGES

Neither 360 nor Fiber/Cayer shall be liable to Urbanlink, and Urbanlink shall
not be liable to either 360 or Fiber/Cayer, for any special, indirect, punitive,
or consequential damages including, but not limited to, loss of profits or
revenue, cost of capital, or claims of contractors, suppliers, clients or
customers (whether arising out of transmission interruptions or problems, any
interruption or degradation of service, or otherwise), whether foreseeable or
not, arising out of, or in connection with, any breach of this Agreement or any
document delivered pursuant to this Agreement, or breach of contract, breach of
warranty, tort, negligence, strict liability or any other theory of liability
relating to the subject matter of this Agreement or of any other document
delivered pursuant to this Agreement, or to the liable party's performance or
non-performance of its obligations under this Agreement or any document
delivered pursuant to this Agreement, and all claims with respect to such
indirect, punitive or consequential damages are hereby specifically waived and
released.

5.7      LIMIT ON DAMAGES

Notwithstanding any other provision of this Agreement, Fiber/Cayer shall not be
liable to Urbanlink for any breach hereof, or any claim of any nature
whatsoever, in excess of 10% of the Project Costs for the Project in respect of
which the claim is made. This Section shall not form the basis of any claim
against Fiber/Cayer in and of itself, and shall not increase or enlarge the
liability of Fiber/Cayer established pursuant to the other terms of this
Agreement or otherwise.

5.8      TIME LIMITATION

Urbanlink shall not make any claim for losses or damages whatsoever in
connection with this agreement more than two years after the date that the event
giving rise to such claim is known or reasonably should have been known to
Urbanlink.

5.9      TAXES

The parties agree to negotiate in good faith with a view to minimizing any taxes
that may be due or become due in connection with the Projects. The parties
acknowledge that this may involve, among other things, amendments to the terms
of this Agreement. Notwithstanding the foregoing, all taxes, assessments or
other fees associated with the Systems shall be the sole responsibility of


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Urbanlink, including but not limited to all sales taxes and all taxes, other
than taxes measured by net income, imposed on Fiber/Cayer or 360 with respect to
the sale, lease, ownership, use or operation of the System. All taxes required
by applicable law to be paid or remitted by Fiber/Cayer or 360 shall be
separately stated on invoices or statements to Urbanlink to the extent permitted
by applicable law.

5.10     INSURANCE

For each Project, Fiber/Cayer and Urbanlink shall each obtain and maintain such
insurance coverage as may then be agreed between Fiber/Cayer and Urbanlink,
acting reasonably and in good faith.

5.11     CONFIDENTIALITY

The parties understand and agree that this Agreement, any documents delivered
pursuant to this Agreement, and all materials, maps, engineering designs and
documents, construction techniques, pricing and other information as may be
necessarily exchanged between them in fulfilling the provisions and intents of
this Agreement, are and shall be confidential. For greater clarity, the
obligations of the parties shall extend to and include all such information as
may be supplied by the grantors of Underlying Rights, and whether directly
supplied by such grantor or supplied by any party. Each party shall ensure that
its Subsidiaries, Affiliates, Associates, directors, officers and employees
shall keep secret all such confidential information of the other party and all
other information which has been clearly identified in advance as confidential
by the other party including, without limitation, this Agreement, shall not
disclose any such confidential information except as authorized by the other
party and shall not use such confidential information except in connection with
this Agreement. This obligation shall continue to bind any party after it shall
cease to be a party for whatever reason and shall survive termination of this
Agreement but such obligation of confidentiality shall not apply:

         (a)      to a disclosure to a person who knew the confidential
                  information prior to its being disclosed;

         (b)      to a disclosure of information which comes into the public
                  domain without any breach of the provisions of this Section;

         (c)      to disclosure of information which is disclosed on a
                  confidential basis to consultants or advisers of a party who
                  have a bona fide need to know to assist that party in the
                  carrying out of the terms of this Agreement;

         (d)      to a disclosure of information which is disclosed to any
                  governmental authority or court having jurisdiction over any
                  aspect of the performance of this Agreement;

         (e)      to a disclosure of information which is disclosed in
                  arbitration, regulatory or court proceedings taken by either
                  party for the enforcement of any of its rights and remedies
                  under this Agreement;

         (f)      to a disclosure in performance of one's obligations (or those
                  of its Affiliates) as a public company;


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         (g)      to a disclosure in connection with the sale or other transfer
                  of rights or strands, to a proposed acquirer of such rights or
                  strands provided the proposed acquirer has executed an
                  appropriate form of confidentiality agreement; or

         (h)      to a disclosure on a confidential basis in connection with
                  any financing.

5.12     PATENTS AND COPYRIGHTS

Urbanlink acknowledges the rights of Fiber/Cayer, 360 and certain Affiliates of
360 to certain patents, copyrights and materials that Fiber/Cayer may use in the
performance of its obligations under this Agreement, acknowledges that is has no
interest in such rights and that no interest in such rights passes under this
Agreement or in any other manner, and agrees to use its reasonable efforts to
protect such rights in dealing with third parties.

                                   ARTICLE 6
                               COSTS AND BENEFITS

6.1      PROJECT COSTS

As its contribution to a Project, Fiber/Cayer shall pay * Project Costs of the
Project.

6.2      LEGAL TITLE AND RIGHT OF USE

Upon completion of each material segment of a Project and payment of *
Project Costs pursuant to Section 6.1, title in such segment shall pass to
Urbanlink, subject to Fiber/Cayer's right to retain in accordance with
Section 6.4 hereof * proceeds from the sale, lease, granting of IRU's or any
similar interests with respect to, or other commercial exploitation of, *
strands of the system constructed by Fiber/Cayer. The * strands retained by
Urbanlink shall be specifically identified by Fiber/Cayer and Urbanlink upon
the completion of a segment (such * strands are herein called the "Class A
Assets", and all of the telecommunications facilities of the System, other
than the Class A Assets, are herein called the "Class B Assets"). To ensure
that Urbanlink remits such proceeds to Fiber/Cayer, Urbanlink shall grant to
Fiber/Cayer an IRU in the Class B Assets. Fiber/Cayer agrees to surrender
this IRU upon receipt of the proceeds from the commercial exploitation of the
Class B Assets or to surrender or assign the same to Urbanlink upon Urbanlink
paying Fiber/Cayer the fair market value of the Class B Assets.

6.3      * OF THE CLASS B ASSETS

Urbanlink shall use Reasonable Efforts to * the Class B Assets, at *. If so
required by notice in writing from Fiber/Cayer, Urbanlink shall * all or any
part of the Class B Assets specified in such notice to the person or persons
specified in such notice * specified in such notice.

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6.4      DEEDS OF SALE

* proceeds from the sale, lease, granting of IRUs or similar interests or
other exploitation of the Class B Assets, less a margin of *, shall be paid
by Urbanlink to Fiber/Cayer forthwith on the receipt of such proceeds by
Urbanlink.

6.5      INTEREST IN DEFAULT

If Urbanlink fails to pay to Fiber/Cayer any amount when such payment is due,
Urbanlink shall also pay to Fiber/Cayer interest on the unpaid amount from the
date payment is due until the date payment is made at a rate equal to 1.5% per
month, compounded monthly (equivalent to 19.56% per annum).

6.6      SECURITY AGREEMENT

If, in the opinion of Fiber/Cayer, acting reasonably and in good faith, it is
necessary or desirable that Urbanlink grant to Fiber/Cayer a security interest
in the Class B Assets, then Urbanlink shall execute and deliver to Fiber/Cayer a
security agreement in such form and on such terms as Fiber/Cayer may request,
acting reasonably and in good faith.

                                   ARTICLE 7
                              TERM AND TERMINATION

7.1      TERM

The terms of this Agreement will commence on the date of this Agreement and will
continue for ten years.

7.2      SURVIVAL OF TERMS

Sections 4.1, 4.2, 5.2, 5.6, 5.7, 5.8, 5.9, 5.11, 5.12, 6.2, 6.3, 6.4, 6.5, 7.2
and 8.1 to 8.17 inclusive shall survive the expiration or termination of this
Agreement and will remain in full force and effect following such expiration or
termination. The expiration or termination of this Agreement will not affect the
rights of any party to make a claim for damages arising from a breach of any
provision of this Agreement which occurred prior to such expiration or
termination.

                                   ARTICLE 8
                                     GENERAL

8.1      DISPUTE RESOLUTION

If the parties are unable to resolve any disagreement or dispute arising under
or relating to this Agreement including, without limitation, the failure to
agree upon any item requiring the mutual agreement of the parties hereunder,
they shall resolve the disagreement or dispute as follows:

         (a)      The parties shall first attempt to settle such dispute by
                  mutual discussion between the members of the project team.


*  Material omitted and filed separately with the Securities and Exchange
   Commission pursuant to a request for confidential treatment under Rule 246-2
   of the Securities Exchange Act of 1934, as amended.


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         (b)      If the matter has not been resolved by the mutual discussion
                  required by subsection (a) within 30 Business Days after the
                  date on which the dispute arose, then the parties shall
                  attempt to settle such dispute by mutual discussion between
                  the President of Urbanlink and the President or a Senior
                  Vice-President of 360.

         (c)      If the matter has not been resolved by the mutual discussion
                  required by subsection (b) within 60 Business Days after which
                  the dispute arose, then such dispute shall finally be resolved
                  by arbitration pursuant to Section 8.2 of this Agreement.

8.2      ARBITRATION

All disputes arising out of or in correction with this contract, or in respect
of any defined legal relationship associated therewith or derived therefrom
(except for disputes arising out of the terms provided in Schedule A), shall be
referred to and finally resolved by arbitration under the Rules of the British
Columbia International Commercial Arbitration Centre. The appointing authorities
shall be the British Columbia International Commercial Arbitration Centre. The
case shall be administered by the British Columbia International Commercial
Arbitration Centre in accordance with its "Procedures for Cases Under the BCICAC
Rules". The place of arbitration shall be Vancouver, British Columbia, Canada.

8.3      GOVERNING LAW AND ATTORNMENT

This Agreement will be governed by and construed in accordance with the
substantive laws of British Columbia and the federal laws of Canada applicable
in British Columbia, without regard to the conflict of law rules of British
Columbia. Subject to Section 8.2, the parties irrevocably submit to and accept
generally and unconditionally the exclusive jurisdiction of the courts and
appellate courts of British Columbia with respect to any legal action or
proceeding which may be brought at any time relating in any way to this
Agreement. Each of the parties irrevocably waives any objection it may now or in
the future have to the venue of any such action or proceeding, and any claim it
may now or in the future have that any such action or proceeding has been
brought in an inconvenient forum.

8.4      TIME OF THE ESSENCE OF THE AGREEMENT

Unless otherwise specifically provided in this Agreement, time will be of the
essence of this Agreement and of the transactions contemplated by this
Agreement.

8.5      REMEDIES NOT EXCLUSIVE

The remedies provided to the parties under this Agreement are cumulative and not
exclusive to each other, and any such remedy will not be deemed or construed to
affect any right which any of the parties is entitled to seek at law, in equity
or by statute.


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8.6      NOTICES

Any notice, direction, request or other communication required or contemplated
by any provision of this Agreement will be given in writing and will be given by
delivering or faxing or emailing the same to the parties as follows:

         (a)      To 360 at:

                  Suite 1500, 1066 West Hastings Street
                  Vancouver, B.C. V6E 3X1

                  Attention:        Catherine McEachern
                  Fax No.:          (604) 681-0994
                  Email:            catherine.mceachern@360.net

         (b)      To Fiber/Cayer at:

                  Suite 1500,1066 West Hastings Street
                  Vancouver, B.C. V6E 3X1

                  Attention:        Catherine McEachern
                  Fax No.;          (604) 681-0994
                  Email:            catherine.mceachern@360.net

         (c)      To Urbanlink at:

                  Suite 1000, 1066 West Hastings Street
                  Vancouver, B.C. V6E 3X1

                  Attention:        Ray Hazlett
                  Fax No.:          (604) 681-5372
                  Email:            ray.hazlett@ledcor.com

Any such notice, direction, request or other communication will be deemed to
have been given or made on the date on which it was delivered or, in the case of
fax or email, on the next business day after receipt of transmission. Any party
may change its fax number or address for service or email address from time to
time by written notice in accordance with this section.

8.7      ASSIGNMENT

         (a)      This Agreement is not assignable by Urbanlink in whole or in
                  part without the prior written consent of 360, such consent
                  not to be unreasonably delayed. This Agreement is not
                  assignable by 360 or Fiber/Cayer without the prior written
                  consent of Urbanlink, such consent not to be unreasonably
                  delayed. Any attempt by any party to assign any of the rights
                  or to delegate any of the duties or obligations of this
                  Agreement without such prior written consent is void.


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         (b)      Notwithstanding the foregoing, the interests of any party may
                  be assigned by such party to an Affiliate, provided that such
                  Affiliate delivers to the other parties a written undertaking
                  to be bound by the provisions of this Agreement in all
                  respects and to the same extent as the assignor is bound and
                  provided further that the assignor will continue to be bound
                  by all the obligations hereunder as if such assignment had not
                  occurred and shall perform such obligations to the extent that
                  such Affiliate fails to do so.

         (c)      Notwithstanding the foregoing, the interests of a party under
                  this Agreement (including, without limitation, in the case of
                  Fiber/Cayer, the right to receive any and all amounts payable
                  to Fiber/Cayer under this Agreement) may be assigned by such
                  party by way of collateral security to a lender without the
                  consent of the other parties, provided however that any such
                  lender agrees in writing that:

                  (i)      the rights and interest of the lender are subject to
                           the rights and interests of the parties other than
                           the assignor under this Agreement;

                  (ii)     prior to realizing on such collateral security it
                           will provide notice to the other parties giving them
                           the opportunity to cure the default; and

                  (iii)    should such security be realized with the result that
                           the title or interest of the assignor, as the case
                           may be, is vested in an assignee, acquirer or other
                           successor in title or interest (including the lender
                           if such is the case) ("Successor"), then the lender
                           will cause such Successor to enter into a written
                           agreement with the other parties to be bound by the
                           provisions of this Agreement in all respects and to
                           the same extent as the assignor was bound and this
                           from the date the title or interest is transferred
                           and provided further that the assignor will continue
                           to be bound by all the obligations under this
                           Agreement as if such transfer of title or interest
                           had not occurred and will perform such obligations to
                           the extent that the Successor fails to do so.

8.8      WAIVER

No failure or delay on the part of any party in exercising any power or right
under this Agreement will operate as a waiver of such power or right. No single
or partial exercise of any right or power under this Agreement will preclude any
further or other exercise of such right or power. No modification or waiver of
any provision of this Agreement and no consent to any departure by any party
from any provision of this Agreement will be effective until the same is in
writing. Any such waiver or consent will be effective only in the specific
instance and for the specific purpose for which it was given. No notice to or
demand on any party in any circumstances will entitle such party to any other or
further notice or demand in similar or other circumstances.


                                     - 14 -
<PAGE>


8.9      FURTHER ASSURANCES

Each of the parties will promptly execute and deliver to the other at the cost
of the other such further documents and assurances and take such further actions
as the other may from time to time request in order to more effectively carry
out the intent and purpose of this Agreement and to establish and protect the
rights, interests and remedies intended to be created in favour of the other.

8.10     ENTIRE AGREEMENT

This Agreement and any documents and agreements to be delivered pursuant to this
Agreement supersede all previous invitations, proposals, letters,
correspondence, negotiations, promises, agreements, covenants, conditions,
representations and warranties with respect to the subject matter of this
Agreement. There is no representation, warranty, collateral term or condition or
collateral agreement affecting this Agreement, other than as expressed in
writing in this Agreement.

8.11     AMENDMENTS

No change or modification of this Agreement will be valid unless it is in
writing and signed by each party to this Agreement.

8.12     INVALIDITY OF PARTICULAR PROVISIONS

If any provision of this Agreement or any part of any provision (in this section
called the "Offending Provision") is declared or becomes unenforceable, invalid
or illegal for any reason whatsoever including, without limiting the generality
of the foregoing, a decision by any competent courts, legislation, statutes,
bylaws or regulations or any other requirements having the force of law, then
the remainder of this Agreement will remain in full force and effect as if this
Agreement had been executed without the Offending Provision.

8.13     CURRENCY

Unless otherwise specified all sums of money expressed in this Agreement are in
the lawful money of Canada.

8.14     NUMBER AND GENDER

Unless the context of this Agreement otherwise requires, to the extent necessary
so that each clause will be given the most reasonable interpretation, the
singular number will include the plural and vice versa, the verb will be
construed as agreeing with the word so substituted, words importing the
masculine gender will include the feminine and neuter genders, words importing
persons will include firms and corporations and words importing firms and
corporations will include individuals.


                                     - 15 -
<PAGE>


8.15     HEADINGS AND CAPTIONS

The headings and captions of sections and paragraphs contained in this Agreement
are all inserted for convenience of reference only and are not to be considered
when interpreting this Agreement.

8.16     ACKNOWLEDGEMENT OF RECEIPT

Each of the parties acknowledges receiving an executed copy of this Agreement.

8.17     PERFORMANCE

360Cayer shall perform all of Fiber/Cayer's obligations under this Agreement in
Quebec, and 360fiber shall perform all of Fiber/Cayer's obligations outside of
Quebec.

8.18     AMENDED AND RESTATED AGREEMENT

This Agreement is an amended and restated version of the original Co-Development
Agreement dated as of April 17, 2000 and made between the undersigned parties.
The parties acknowledge and agree that the original Co-Development Agreement is
superceded by the terms of this Amended and Restated Co-Development Agreement,
with effect as of the date of this Agreement. For greater clarity and the
avoidance of doubt, the original Co-Development Agreement shall continue to have
effect to govern the rights and obligations of the parties for the period from
April 17, 2000 to the expiry of the day before the date of this Agreement.

8.19     ENUREMENT

Subject to the restrictions on transfer contained in this Agreement, this
Agreement will enure to the benefit of and be binding on the parties and their
respective heirs, executors, administrators, successors and assigns.

                     [THE NEXT PAGE IS THE EXECUTION PAGE.]



                                     - 16 -
<PAGE>


IN WITNESS WHEREOF the parties have executed this Agreement as of the date
stated on the first page.

360NETWORKS INC.                       360FIBER LTD.
Per:                                   Per:
Signed                                 Signed
----------------------------           ----------------------------
Signature                              Signature

WFI URBANLINK LTD.                     360CAYER LTEE.
Per:                                   Per:
Signed                                 Signed
----------------------------           ----------------------------
Signature                              Signature



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