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                                                                   Exhibit 10.10

                              COOPERATION AGREEMENT

     THIS COOPERATION AGREEMENT ("Cooperation Agreement" or "Agreement") is made
this     day of December, 2003, by and between Global Crossing Limited (formerly
     ---
GC Acquisition Ltd.) ("New Global Crossing"), and the individuals signatory
hereto in their capacities as Estate Representative under the Plan (the "Estate
Representative") and as, or on the behalf of, the Liquidating Trustee under the
Liquidating Trust Agreement (the "Liquidating Trustee"), and not in their
individual capacities (all references to the Estate Representative herein shall
mean the Estate Representative or the Liquidating Trustee, as the case may be).

                                    RECITALS

     WHEREAS, Global Crossing Ltd., a Bermuda corporation ("Old Global
Crossing"), and 79 of its direct and indirect subsidiaries (the "US Debtors")
commenced reorganization cases by filing petitions for relief under Chapter 11
of title 11 of the United States Code, 11 U.S.C. (S) 101-1330 (as amended, the
"Bankruptcy Code") in the United States Bankruptcy Court for the Southern
District of New York (the "Bankruptcy Court");

     WHEREAS, GCL and 15 of its direct and indirect subsidiaries (the "Bermuda
Debtors" and together with the U.S. Debtors, the "Debtors") commenced
restructuring proceedings before the Supreme Court of Bermuda (the "Bermuda
Court");

     WHEREAS, on October 28, 2002 the US Debtors filed their Joint Plan of
Reorganization under Chapter 11 of the Bankruptcy Code (as amended, modified and
supplemented from time to time, the "Plan"), which has been confirmed by an
order of the Bankruptcy Court dated December 26, 2002 (the "Confirmation
Order");

     WHEREAS, the Bermuda Debtors each filed a Scheme of Arrangement with the
Bermuda Court, which have been sanctioned by an order of the Bermuda Court dated
January 3, 2003 (the "Sanction Order") (the "Schemes of Arrangement");

     WHEREAS, the terms of the Schemes of Arrangement provide for the treatment
of claims against the Bermuda Debtors and all distributions to creditors of the
Bermuda Debtors to be made in accordance with the terms of the Plan;

     WHEREAS, the Plan provides for the sale of substantially all of the
Debtors' assets, other than, among other things, the Liquidating Trust Assets,
and the transfer of the Reorganized Subsidiary Debtors to the Investors pursuant
to the terms of the Purchase Agreement;

     WHEREAS, New Global Crossing is the parent entity of Global Crossing
Holdings Limited ("New GCHL") and the Reorganized Subsidiary Debtors and as of
the date hereof has control of the books, records and current employees of New
GCHL and the Reorganized Subsidiary Debtors;

     WHEREAS, the Plan provides for the establishment of a liquidating trust to
resolve, liquidate and realize upon the Liquidating Trust Assets;

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     WHEREAS, the Plan provides for the appointment and selection of the Estate
Representative to act as trustee of the Liquidating Trust and to undertake
certain other functions under the Plan, in furtherance of and consistent with
the purpose of the Plan, the Liquidating Trust Agreement and the Schemes of
Arrangement, with the power and authority to prosecute, compromise and settle
objections to Disputed Claims; to commence, pursue, compromise and settle Estate
Representative Claims; and to perform such other duties as may be vested in or
assumed by the Estate Representative pursuant to the Plan, the Liquidating Trust
Agreement and the Schemes of Arrangement (the "Estate Representative
Obligations");

     WHEREAS, Section 1.3 of the Liquidating Trust Agreement provides that New
Global Crossing shall deliver certain documents to the Estate Representative in
connection with the Estate Representative Claims;

     WHEREAS, New Global Crossing has advised that it will be unable to deliver
such documents on the Effective Date; and

     WHEREAS, among other things, execution of this Cooperation Agreement is
intended to satisfy New Global Crossing's obligation to deliver such documents;

     NOW THEREFORE, in consideration of the above-stated premises, the mutual
covenants contained herein, in the Plan, in the Liquidating Trust Agreement and
in the Schemes of Arrangement and for other good and valuable consideration, New
Global Crossing and the Estate Representative agree as follows:

                                   ARTICLE I

                                   DEFINITIONS

     1.1. Defined Terms. Capitalized terms used in this Cooperation Agreement
and not otherwise defined herein shall have the meanings ascribed to them in the
Plan or in the Bankruptcy Code. The words "herein," "hereof," "hereto,"
"hereunder," and others of similar import refer to this Cooperation Agreement as
a whole and not to any particular article, section, subsection, or clause
contained in this Cooperation Agreement. Wherever from the context it appears
appropriate, each term stated in either the singular or the plural shall include
the singular and the plural and pronouns stated in the masculine, feminine or
neuter gender shall include the masculine, the feminine and the neuter.

                                   ARTICLE II

                  OBLIGATIONS AND RIGHTS OF NEW GLOBAL CROSSING

     2.1. Cooperation. On and after the Effective Date, New Global Crossing
agrees to, and to cause New GCHL and the Reorganized Subsidiary Debtors to,
cooperate with the Estate Representative in connection with the Estate
Representative's discharge of its duties under the Plan, the Liquidating Trust
Agreement and the Schemes of Arrangement by:

     (a)  providing reasonable access to such employees of New Global Crossing,
          New GCHL and the Reorganized Subsidiary Debtors as the Estate
          Representative

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          deems reasonably necessary to fulfill the Estate Representative
          Obligations. For purposes of the foregoing, access shall include,
          without limitation, access by telephone, periodic meetings,
          interviews, and appearance of such employees as witnesses (by
          affidavits, at depositions and trials, as necessary) and availability
          for preparation as a witness in any proceedings wherever situated;

     (b)  providing access to and delivering to the Estate Representative any
          and all documents, instruments, books and records required to be
          delivered to the Liquidating Trustee on the Effective Date pursuant to
          the terms of the Liquidating Trust Agreement in connection with the
          Estate Representative Claims or as the Estate Representative deems
          reasonably necessary to fulfill the Estate Representative Obligations,
          whether held by New Global Crossing, New GCHL or a Reorganized
          Subsidiary Debtor, their agents, advisors, attorneys, accountants or
          any other professional hired by the Debtors, New Global Crossing, New
          GCHL or a Reorganized Subsidiary Debtor (the "Documents") (including
          those maintained in electronic format and original documents), which
          Documents shall include without limitation personnel records,
          accounting records, customer and vendor lists and records, management
          reports, minutes of meetings of the Board of Directors of the Debtors,
          minutes of meetings of the shareholders of the Debtors, e-mail
          records, contracts, financial records, reports and any and all other
          work product generated by the Debtors' agents and professionals, and
          any and all communications with Debtors' agents and professionals,
          whether or not covered by the attorney work product, attorney-client,
          or any other privileges, and documents and other instruments relating
          to payments for goods and services (i.e. invoices, purchase orders,
          checks, requisitions, etc.), provided that New Global Crossing shall
          not be responsible for the delivery of such Documents that may have
          been lost (after undertaking reasonable good faith efforts to find) or
          destroyed prior to the Effective Date;

     (c)  providing such other reasonable information and access to employees
          upon request as the Estate Representative deems reasonably necessary
          to fulfill its responsibilities under the Plan, the Liquidating Trust
          Agreement and the Schemes of Arrangement; and

     (d)  otherwise cooperating with the Estate Representative in fulfilling the
          Estate Representative Obligations as contemplated by the Plan, the
          Liquidating Trust Agreement and the Schemes of Arrangement.

All references in this section 2.1 (and elsewhere in this Agreement) to
cooperation and similar obligations running in favor of the Estate
Representative, shall be deemed also to run in favor of the Estate
Representative's agents and representatives retained by the Estate
Representative to discharge the Estate Representative Obligations (including,
for example, counsel, accountants and financial advisors).

     2.1.1. The parties agree to work constructively together to structure the
access and delivery requirements of clauses 2.1 (a) through (d) above, so as not
to materially detract from New Global Crossing's ability to conduct its business
operations (including the operations of

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New GCHL and the Reorganized Subsidiary Debtors); provided, however that it is
understood and agreed that New Global Crossing, New GCHL and the Reorganized
Subsidiary Debtors shall at all times use reasonable efforts to provide such
assistance in a timely manner, so as to enable the Estate Representative to
timely pursue the Estate Representative Claims and otherwise timely fulfill
their Estate Representative Obligations, it being understood that time may be of
the essence in certain instances where the Estate Representative is under
deadlines in connection with certain statutes of limitation or court hearing or
filing deadlines.

     2.1.2. New Global Crossing hereby designates the following two (2)
employees to serve as contacts for the Estate Representative, facilitating the
Estate Representative's access to employees and information (including the
Documents) provided for in this Agreement (each a "Cooperation Coordinator"):
[David Sheffey and Frank Fields]. The Cooperation Coordinators shall designate
an alternate to deal with requests for access and information when neither
Cooperation Coordinator is available. New Global Crossing shall require the
Cooperation Coordinators and their alternate to facilitate the cooperation
contemplated by this Agreement in accordance with the terms hereof. To the
extent practicable, all requests for information, documentation or access to New
Global Crossing employees (including employees of New GCHL and the Reorganized
Subsidiary Debtors) will be made to a Cooperation Coordinator, or if not
available, the alternate. Nothing herein shall preclude the Estate
Representative from making requests to counsel to New Global Crossing, or from
seeking information from sources other than the Cooperation Coordinators or the
alternate, if such persons are not available or do not otherwise provide the
information or access requested in a timely manner.

     2.1.3. Notwithstanding anything in this Agreement to the contrary, the
parties acknowledge and agree that (a) nothing herein shall prohibit the Estate
Representative from obtaining access to information, Documents or employees that
they otherwise would be entitled to by subpoena or other legal process without
regard to this Agreement and (b) New Global Crossing need not comply with the
terms of this Agreement to the extent that any requests of the Estate
Representative relate to or involve Claims (as defined in the Purchase
Agreement) that are excluded from clauses (iv) or (v) of the definition of
Assets (as defined in the Purchase Agreement) by operation of the second proviso
paragraph to that definition.

     2.2. Other Documents. In the event all of the Documents were not turned
over to the Estate Representative on or prior to the Effective Date, New Global
Crossing shall provide all such Documents to the Estate Representative at no
cost to the Liquidating Trust within 30 days after the date of the Estate
Representative's request of such documents or such later date as agreed to by
the parties. The parties acknowledge that the execution of this Agreement by New
Global Crossing and the performance of New Global Crossing's obligations
hereunder are intended to satisfy the obligations of New Global Crossing as set
forth in Section 1.3(b) of the Liquidating Trust Agreement.

     2.3. Further Actions. At any time and from time to time after the Effective
Date, New Global Crossing (including New GCHL and the Reorganized Subsidiary
Debtors) agrees (a) at the reasonable request of the Estate Representative to
execute and deliver any instruments or documents, and (b) to take, or cause to
be taken, all such further action as the Estate Representative may reasonably
request in order to evidence or effectuate the transfer of the Liquidating Trust
Assets to the Liquidating Trust and consummation of the transactions

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contemplated by the Plan, the Liquidating Trust Agreement and the Schemes of
Arrangement and to otherwise carry out the intent of the Plan, the Liquidating
Trust Agreement and the Schemes of Arrangement.

     2.4. Preservation of Privilege and Defenses. In connection with the rights,
claims, and causes of action that constitute the Liquidating Trust Assets, any
attorney-client privilege, work-product privilege, or other privilege or
immunity attaching to any documents or communications (whether written or oral)
transferred to the Liquidating Trust or provided to the Estate Representative on
behalf of the Liquidating Trust shall vest in the Estate Representative and its
representatives, and New Global Crossing, New GCHL, the Reorganized Subsidiary
Debtors and the Estate Representative are authorized to take all necessary
actions to effectuate the transfer of such privileges and available defenses.

                                  ARTICLE III

               OBLIGATIONS AND RIGHTS OF THE ESTATE REPRESENTATIVE

     3.1. Cooperation Coordinators. The Estate Representative agrees that in
fulfilling the Estate Representative Obligations it will make requests for
access to employees, documents and other information to the Cooperation
Coordinators as provided and subject to the exceptions set forth in Section
2.1.2.

     3.2. Standards. The Estate Representative shall use commercially reasonable
efforts to limit its requests of New Global Crossing hereunder to the Estate
Representative's needs that cannot otherwise be satisfied from information and
documents already in the custody, possession or control of the Estate
Representative. The Estate Representative will seek access to employees only
during normal business hours unless otherwise agreed by the parties.

     3.3. Reimbursement of Certain Expenses. Except as set forth below with
respect to requests relating the production of Documents ("Document Requests"),
the Estate Representative shall reimburse New Global Crossing (or as directed by
New Global Crossing, New GCHL or a Reorganized Subsidiary Debtor) out of the
Estate Representative Expense Fund or the Liquidating Trust Assets, as
applicable, in connection with the Estate Representative's requests hereunder,
including gaining access to employees for the purposes of interviewing such
employees or to have such employees testify at depositions or in Court
proceedings. In connection with such requests, the Estate Representative shall
reimburse New Global Crossing for any such employee's out of pocket travel costs
and for such employee's time for the hours of access or service provided, with
such time reimbursement to be based New Global Crossing's actual costs incurred
in connection with the performance of its obligations hereunder (e.g., such
employee's salary). In no event, unless otherwise agreed to by the Estate
Representative, shall the Estate Representative be required to reimburse New
Global Crossing for any costs associated with Document Requests (including
copying and shipping costs and the time of any employees associated with
responding to Document Requests) pursuant to the terms hereof.

     3.4. Maintenance of Documents and Information. The Estate Representative or
the Liquidating Trustee, as the case may be, shall be entitled to maintain, use,
share, disclose, and rely on all of the Documents and information obtained from
New Global Crossing and its

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employees hereunder to the same extent and in the same manner as provided in the
Liquidating Trust Agreement.

     3.5. Use of Consultants and Contractors. The Estate Representative
acknowledges that certain information may be in the possession of certain
professionals and other contractors of New Global Crossing. Nothing herein is
intended to preclude the Estate Representative from hiring those consultants and
contractors to the extent that the Estate Representative reasonably deems such
retention to be necessary or appropriate in order to fulfill the Estate
Representative Obligations. If the Estate Representative hires any such
professional, New Global Crossing shall be responsible for the out-of-pocket
expenses reasonably incurred by any such professional in connection with the
delivery of Documents by said professional, upon request of the Estate
Representative, to the extent not already within the Estate Representative's
possession, in accordance with the terms of this Agreement. Nothing herein is
intended to require the Estate Representative to hire any such professional in
order to gain access to any Documents, as New Global Crossing is obligated to
deliver any such Documents in the possession of any such professionals and other
contractors pursuant to section 2.1 (b) hereof Notwithstanding the foregoing, if
the Estate Representative hires any such professional, New Global Crossing shall
not be responsible for any other costs of such professional.

                                   ARTICLE IV

                             TERM OF THIS AGREEMENT

     4.1. General. This Agreement shall have an initial term of three (3) years
from the date hereof. Such initial term may be extended by the Estate
Representative for successive one (1) year periods upon notice to New Global
Crossing that the Estate Representative believes, in the exercise of its
reasonable business judgment, that the Estate Representative continues to need
the benefit of this Agreement in order to carry out its duties.

                                   ARTICLE V

                                  MISCELLANEOUS

     5.1. Notices. All notices, requests or other communications required or
permitted to be made in accordance with this Cooperation Agreement to the Estate
Representative shall be given in writing (delivered by hand or by certified
mail, return receipt requested), or by telecopy.

     5.2. Effectiveness. This Cooperation Agreement shall become effective on
the Effective Date of the Plan.

     5.3. Counterparts. This Cooperation Agreement may be executed in one or
more counterparts, all of which shall be taken together to constitute one and
the same instrument.

     5.4. Governing Law. Except to the extent governed by the Bankruptcy Code,
this Cooperation Agreement shall be governed by, construed under and interpreted
in accordance with, the laws of the State of New York.

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     5.5. Exclusive Jurisdiction and Standing. As provided in Section 11.1 of
the Plan, the Bankruptcy Court has exclusive jurisdiction over all
controversies, suits and disputes that may arise under this Cooperation
Agreement.

     5.6. Severability. The terms and provisions of this Cooperation Agreement
shall be deemed severable, and in the event any term or provision hereof or any
portion thereof is deemed or held to be invalid, illegal or unenforceable, the
remaining terms and provisions hereof and portions thereof shall nevertheless
continue and be deemed to be in full force and effect. Any provision of this
Cooperation Agreement which is prohibited or unenforceable in any jurisdiction
shall not invalidate the remaining provisions hereof, and any such prohibition
or unenforceability in any jurisdiction shall not invalidate or render
unenforceable any such provision in any other jurisdiction.

     5.7. Independent Contractor Status. New Global Crossing shall be deemed to
be an independent contractor of the Estate Representative and employees of New
Global Crossing shall at all times be regarded as employees of New Global
Crossing. Nothing contained in this Cooperation Agreement shall create or be
deemed to create an employment, agency, joint venture or partnership
relationship between the Estate Representative on the one hand, and New Global
Crossing or any of its employees, on the other hand.

     5.8. No Waiver. New Global Crossing and the Estate Representative agree
that no failure or delay by either party in exercising any right, power or
privilege hereunder will operate as a waiver thereof, and that no single or
partial exercise thereof will preclude any other or further exercise thereof or
the exercise of any right, power and privilege hereunder.

     5.9. Entire Agreement. This Cooperation Agreement contains the entire
agreement of the parties concerning the subject matter hereof, and no
modification of this Cooperation Agreement or waiver of the terms and conditions
hereof will be binding upon the parties unless approved in writing by the
parties.

     5.10. Authorization. Each of the undersigned individuals represents and
warrants that he/she has the power and authority to enter into this Cooperation
Agreement and bind their respective companies or trust as its authorized
representatives.

     5.11. Titles. The section titles used herein are for convenience only and
shall not be considered in construing or interpreting any of the provisions of
this Cooperation Agreement.

     5.12. Binding Effect. The parties agree that this Cooperation Agreement is
for the benefit of and shall be binding upon the parties and their respective
representatives, transferees, successors and assigns.

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     IN WITNESS WHEREOF, the parties hereto have executed this Cooperation
Agreement or caused this Cooperation Agreement to be duly executed by their
respective representatives thereunto duly authorized as of the day and year
first above written.

Global Crossing Limited (formerly GC Acquisition Ltd.)


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Estate Representative


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