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                                                                  EXHIBIT 10.29

FORM

                                    GUARANTY

          This GUARANTY, dated as of October __, 2002, by FLAG TELECOM HOLDINGS
LIMITED, a Bermuda corporation, and its permitted successors or assigns ("FLAG
HOLDCO", and with its permitted successors or assigns, "GUARANTOR"), and xxxx,
the holder of that certain Secured Note as hereinafter defined.

                              W I T N E S S E T H:

          WHEREAS, pursuant to that certain Senior Secured Note dated as of the
date hereof, issued by FLAG Asia Limited (the "DEBTOR/PAYOR"), in favor of xxxx
and its registered assigns (xxxx and any registered assigns being referred to
herein as "HOLDER") (including all annexes, exhibits and schedules thereto, as
from time to time amended, restated, supplemented or otherwise modified, the
"SECURED NOTE"), Debtor/Payor has agreed to unconditionally pay the amounts
specified therein; and

          WHEREAS, pursuant to that certain Security Agreement, dated as of the
date hereof, by the Debtor/Payor and the Grantors referred to therein, in favor
of Wilmington Trust Company ("COLLATERAL AGENT"), as collateral agent for the
benefit of itself and xxxx as the Secured Parties (including all exhibits and
schedules thereto, as from time to time amended, restated, supplemented or
otherwise modified, the "SECURITY AGREEMENT"), the Debtor/Payor and Grantors
have granted a Security Interest in the Collateral to secure the Secured
Obligations; and

          WHEREAS, Guarantor is the ultimate parent company of Debtor/Payor and
as such will derive direct and indirect economic benefits from the financial
accommodations provided by Holder to the Debtor/Payor; and

          WHEREAS, in order to induce Holder to accept the Secured Note and
enter into the other Loan Documents, Guarantor has agreed to guarantee payment
of the Secured Note;

          NOW, THEREFORE, in consideration of the premises and the covenants
hereinafter contained, it is agreed as follows:

1.   DEFINITIONS.

          All capitalized terms not specifically defined herein shall have the
meanings ascribed thereto in the Security Agreement. In addition, as used
herein:

          "BUSINESS" means the business of the Debtor/Payor and its Subsidiaries
(as hereinafter defined), and any complimentary or logical extensions of such
business, including, without limitation, any telecommunications or network
services business in any geographic location, but only to the extent permitted
under the Secured Note.

          "BUSINESS DAY" means any day other than a Saturday, Sunday, or other
day on which banking institutions in any of New York, New York, London, England,
and Paris, France are authorized or obligated to close.

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          "EXCLUDED TAXES" means any taxes imposed on or measured by the overall
net income (including a franchise or excise tax based on net income) of the
Holder or the Collateral Agent by the jurisdiction in which it is incorporated,
maintains its principal executive office, conducts its activities, or in which
its office for payment hereunder is located.

          "GAAP" means generally accepted accounting principles as promulgated
by the Financial Accounting Standards Board, as in effect from time to time.

          "GOVERNMENTAL AUTHORITY" means any United States or non-United States
federal, national, supranational, state, provincial, county, city, local or
similar government, governmental, regulatory or administrative authority,
agency, or commission or any court, tribunal, arbitrator, judicial or arbitral
body, or any subdivision of any of the foregoing.

          "GOVERNMENTAL ORDER" means any order, writ, judgment, injunction,
decree, stipulation, determination, administrative ruling or award entered by or
with any Governmental Authority (in each case whether preliminary or final).

          "GUARANTY" means this Guaranty, including all amendments,
modifications and supplements and any annexes, exhibits and schedules to any of
the foregoing, and shall refer to this Guaranty as the same may be in effect at
the time such reference becomes operative.

          "LAW" means any United States or non-United States federal, national,
supranational, state, provincial, county, city, local or similar constitution,
statute, law, ordinance, regulation, rule, code, order, requirement or rule of
law (including, without limitation, common law).

          "LIEN" means any mortgage, pledge, hypothecation, assignment for
security purposes, security interest, encumbrance, lien (statutory or
otherwise), charge or other restriction of any kind, including any agreement to
give any of the foregoing, any conditional sale or other title retention
agreement or lease in the nature thereof, any sale of receivables with recourse
against Guarantor, any financing or similar statement or notice filed under the
Uniform Commercial Code as adopted and in effect in the relevant jurisdiction
(or other similar recording or notice statute, and any lease in the nature
thereof) other than to reflect ownership by a third party of property leased to
the Debtor/Payor under a lease which is not in the nature of a conditional sale
or title retention agreement.

          "LOAN DOCUMENTS" means the Secured Note, the Security Agreement, this
Guaranty, and each other agreement, instrument, document, undertaking or
certificate executed or delivered pursuant to any of the foregoing.

          "PERSON" means an individual, a partnership, a corporation, a limited
liability company, an association, a joint stock company, a trust, a joint
venture, an unincorporated organization, a governmental entity or any
department, agency or political subdivision thereof and any other entity.

          "SECURITIES AND EXCHANGE COMMISSION" includes any governmental body or
agency succeeding to the functions thereof.

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          "SUBSIDIARY" means, with respect to any Person, any corporation,
limited liability company, partnership, association or other business entity of
that Person (i) if a corporation, a majority of the total voting power of shares
of stock entitled (without regard to the occurrence of any contingency) to vote
in the election of directors, managers or trustees thereof is at the time owned
or controlled, directly or indirectly, by that Person or one or more of the
other Subsidiaries of that Person or a combination thereof, or (ii) if a limited
liability company, partnership, association or other business entity, a majority
of the partnership or other similar ownership interest thereof is at the time
owned or controlled, directly or indirectly, by that Person or one or more
Subsidiaries of that Person or a combination thereof. For purposes hereof, a
Person or Persons shall be deemed to have a majority ownership interest in a
limited liability company, partnership, association or other business entity if
such Person or Persons shall be allocated a majority of limited liability
company, partnership, association or other business entity gains or losses or
shall be or control (or have the power to be or control) a managing director,
manager or general partner of such limited liability company, partnership,
association or other business entity.

          "TAX" or "TAXES" means any federal, state, county, local, foreign or
other income, gross receipts, ad valorem, franchise, profits, sales or use,
transfer, registration, excise, utility, environmental, communications, real or
personal property, capital stock, membership interest, license, payroll, wage or
other withholding, employment, social security, severance, stamp, occupation,
alternative or add-on minimum, estimated and other taxes of any kind whatsoever
(including deficiencies, penalties, additions to tax, and interest attributable
thereto) whether disputed or not.

          "TERMINATION DATE" means the date on which all Secured Obligations are
indefeasibly paid in full, in cash, to Holder.

2.   THE GUARANTY.

          2.1    GUARANTY OF GUARANTEED OBLIGATIONS OF DEBTOR/PAYOR. The
Guarantor hereby unconditionally guarantees to the Collateral Agent and Holder,
and its respective successors, endorsees, transferees and assigns (but subject
to the proviso in SECTION 7.6 hereof), the prompt payment when due (whether at
stated maturity, by acceleration or otherwise) and performance of the Secured
Obligations (hereinafter, the "GUARANTEED OBLIGATIONS"). Guarantor agrees that
this Guaranty is a guaranty of payment and performance and not of collection,
and that its obligations under this Guaranty shall be primary, absolute and
unconditional, irrespective of, and unaffected by:

                 (a) the genuineness, validity, regularity, enforceability or
     any future amendment of, or change in this Guaranty, any other Loan
     Document or any other agreement, document or instrument to which
     Debtor/Payor and/or the Guarantor is or may become a party;

                 (b) the absence of any action to enforce this Guaranty or any
     other Loan Document or the waiver or consent by Holder with respect to any
     of the provisions thereof;

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                 (c) the existence, value or condition of, or failure to perfect
     Holder's Lien against, any Collateral for the Guaranteed Obligations or any
     action, or the absence of any action by Holder in respect thereof
     (including, without limitation, the release of any such security);

                 (d) the insolvency of Debtor/Payor; or

                 (e) any other action or circumstances which might otherwise
     constitute a legal or equitable discharge or defense of a surety or
     guarantor;

it being agreed by the Guarantor that its obligations under this Guaranty shall
not be discharged until the Termination Date. The Guarantor shall be regarded,
and shall be in the same position, as principal debtor with respect to the
Guaranteed Obligations. The Guarantor agrees that any notice or directive given
at any time to Holder which is inconsistent with the waiver set forth in this
SECTION 2.1 shall be null and void and may be ignored by Holder and, in
addition, may not be pleaded or introduced as evidence in any litigation
relating to this Guaranty for the reason that such pleading or introduction
would be at variance with the written terms of this Guaranty, unless Holder has
specifically agreed otherwise in writing. It is agreed among the Guarantor and
Holder that the foregoing waivers are of the essence of the transaction
contemplated by the Loan Documents and that, but for this Guaranty and such
waivers, Holder would decline to enter into the Loan Documents.

          2.2    DEMAND BY HOLDER. In addition to the terms of the Guaranty set
forth in SECTION 2.1 hereof, and in no manner imposing any limitation on such
terms, it is expressly understood and agreed that if, at any time, the
outstanding principal amount of the Guaranteed Obligations under the Secured
Note (including all accrued interest thereon) is declared to be immediately due
and payable, then Guarantor shall, without demand, pay the entire outstanding
Guaranteed Obligations due and owing to Holder. Payment by Guarantor shall be
made to Holder in immediately available funds to an account designated by
Holder, at the address set forth herein for the giving of notice to Holder, or
at any other address that may be specified in writing from time to time by
Holder, and shall be credited and applied to the Guaranteed Obligations in
accordance with the Security Agreement.

          2.3    ENFORCEMENT OF GUARANTY. In no event shall Holder have any
obligation (although it is entitled, at its option) to proceed against
Debtor/Payor or any Collateral pledged to secure the Guaranteed Obligations
before seeking satisfaction from the Guarantor, and Holder may proceed, prior or
subsequent to, or simultaneously with, the enforcement of Holder's rights
hereunder, to exercise any right or remedy which it may have against any
Collateral, as a result of any Lien it may have as security for all or any
portion of the Guaranteed Obligations.

          2.4    WAIVER. In addition to the waivers set forth in SECTION 2.1
hereof, Guarantor waives, and agrees that it shall not at any time insist upon,
plead or in any manner whatsoever claim or take the benefit or advantage of, any
appraisal, valuation, stay, extension, marshaling of assets or redemption laws,
or exemption, whether now or at any time hereafter in force, which may delay,
prevent or otherwise affect the performance by Guarantor of its Guaranteed
Obligations under, or the enforcement by Holder of, this Guaranty. Guarantor
hereby waives diligence, presentment and demand (whether for non-payment or
protest or of

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acceptance, maturity, extension of time, change in nature or form of the
Guaranteed Obligations, acceptance of further security, release of further
security, composition or agreement arrived at as to the amount of, or the terms
of, the Guaranteed Obligations, notice of adverse change in Debtor/Payor's
financial condition or any other fact which might increase the risk to
Guarantor) with respect to any of the Guaranteed Obligations or all other
demands whatsoever and waives the benefit of all provisions of law which are or
might be in conflict with the terms of this Guaranty. Guarantor represents,
warrants and agrees that, as of the date of this Guaranty, its obligations under
this Guaranty are not subject to any offsets or defenses against Holder.
Guarantor further agrees that its obligations under this Guaranty shall not be
subject to any counterclaims, offsets or defenses against Holder which may arise
in the future.

          2.5    BENEFIT OF GUARANTY. The provisions of this Guaranty are for
the benefit of Holder and its respective successors, transferees, endorsees and
assigns, and nothing contained herein shall impair the obligations of the
Debtor/Payor under the Loan Documents. In the event that all or any part of the
Guaranteed Obligations are transferred, endorsed or assigned by Holder to any
Person or Persons, any reference to "Holder" herein shall be deemed to refer
equally to such Person or Persons.

          2.6    MODIFICATION OF GUARANTEED OBLIGATIONS, ETC. Guarantor hereby
acknowledges and agrees that Holder (or Collateral Agent as circumstances may
require) may at any time or from time to time, with or without the consent of,
or notice to, Guarantor:

                 (a) [Intentionally omitted];

                 (b) take any action under or in respect of the Loan Documents
     in the exercise of any remedy, power or privilege contained therein or
     available to it at law, equity or otherwise, or waive or refrain from
     exercising any such remedies, powers or privileges;

                 (c) [Intentionally omitted];

                 (d) extend or waive the time for Debtor/Payor's performance of,
     or compliance with, any term, covenant or agreement on its part to be
     performed or observed under the Loan Documents, or waive such performance
     or compliance or consent to a failure of, or departure from, such
     performance or compliance;

                 (e) take and hold Collateral for the payment of the Guaranteed
     Obligations guaranteed hereby or sell, exchange, release, dispose of, or
     otherwise deal with, any property pledged, mortgaged or conveyed, or in
     which Collateral Agent has been granted a Security Interest for the benefit
     of Holder, to secure any Guaranteed Obligations;

                 (f) release anyone who may be liable in any manner for the
     payment of any amounts owed by Guarantor to Holder;

                 (g) modify or terminate the terms of any intercreditor or
     subordination agreement pursuant to which claims of other creditors of the
     Guarantor or Debtor/Payor are subordinated to the claims of Holder; and/or

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                 (h) apply any sums by whomever paid or however realized to any
     amounts owing by the Guarantor to Holder in such manner as Holder shall
     determine in its discretion;

and Holder shall not incur any liability to Guarantor as a result thereof, and
no such action shall impair or release the Guaranteed Obligations of Guarantor
under this Guaranty.

Notwithstanding anything in this Guaranty to the contrary, Guarantor hereby
acknowledges and agrees that the obligations under this Guaranty shall remain in
full force and be unaffected by any change or extension of the manner, place or
terms of payment of, or renewal or alteration of all or any portion of, the
Guaranteed Obligations or any amendment, or modification, of any manner
whatsoever, of any Loan Document other than this Guaranty without regard to the
Guarantor's consent or failure to consent thereto (and without regard to any
notice or any lack of notice provided to Guarantor).

          2.7    REINSTATEMENT. This Guaranty shall remain in full force and
effect and should any petition hereafter be filed by or against Debtor/Payor or
Guarantor for liquidation or reorganization, should Debtor/Payor or Guarantor
hereafter become insolvent or make an assignment for the benefit of creditors or
should a receiver or trustee be appointed for all or any significant part of
Debtor/Payor's or Guarantor's assets. This Guaranty shall continue to be
effective or be reinstated, as the case may be, if at any time payment and
performance of the Guaranteed Obligations, or any part thereof, is, pursuant to
applicable law, rescinded or reduced in amount, or must otherwise be restored or
returned by Holder, whether as a "voidable preference", "fraudulent conveyance",
or otherwise, all as though such payment or performance had not been made. In
the event that any payment, or any part thereof, is rescinded, reduced, restored
or returned, the Guaranteed Obligations shall be reinstated and deemed reduced
only by such amount paid and not so rescinded, reduced, restored or returned.

          2.8    DEFERRAL OF SUBROGATION, ETC. Notwithstanding anything to the
contrary in this Guaranty, or in any other Loan Document, Guarantor hereby:

                 (a) expressly and irrevocably waives, on behalf of itself and
     its successors and assigns until the Termination Date, any and all rights
     at law or in equity to subrogation, to reimbursement, to exoneration, to
     contribution, to indemnification, to set off or to any other rights that
     could accrue to a surety against a principal, to a guarantor against a
     principal, to a guarantor against a maker or obligor, to an accommodation
     party against the party accommodated, to a holder or transferee against a
     maker, or to the holder of any claim against any Person, and which the
     Guarantor may have or hereafter acquire against Holder in connection with
     or as a result of such Guarantor's execution, delivery and/or performance
     of this Guaranty, or any other documents to which such Guarantor is a party
     or otherwise; and

                 (b) acknowledges and agrees (i) that this waiver is intended to
     benefit Holder and shall not limit or otherwise effect Guarantor's
     liability hereunder or the enforceability of this Guaranty, and (ii) that
     Holder and its respective successors and assigns are intended third party
     beneficiaries of the waivers and agreements set forth in

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     this SECTION 2.8 and their rights under this SECTION 2.8 shall survive
     payment in full of the Guaranteed Obligations.

          2.9    ELECTION OF REMEDIES. If Holder or Collateral Agent may, under
applicable law, proceed to realize benefits under any of the Loan Documents
giving Holder or Collateral Agent a Lien upon any Collateral owned by
Debtor/Payor, either by judicial foreclosure or by non-judicial sale or
enforcement, Holder or Collateral Agent, as the case may be, may, at its sole
discretion, determine which of such rights or remedies it may pursue without
affecting any of such rights and remedies under this Guaranty. If, in the
exercise of any of its rights and remedies, Holder or Collateral Agent shall
forfeit any of their rights or remedies, including their right to enter a
deficiency judgment against Debtor/Payor, whether because of any applicable laws
pertaining to "election of remedies" or the like, Guarantor hereby consents to
such action by Holder or Collateral Agent and waives any claim based upon such
action, even if such action by Holder or Collateral Agent shall result in a full
or partial loss of any rights of subrogation which Guarantor might otherwise
have had but for such action by Holder or Collateral Agent. Any election of
remedies which results in the denial or impairment of the right of Holder or
Collateral Agent to seek a deficiency judgment against any Debtor/Payor shall
not impair Guarantor's obligation to pay the full amount of the Guaranteed
Obligations. In the event Holder shall bid at any foreclosure or trustee's sale
or at any private sale permitted by law or the Loan Documents, Holder may bid
all or less than the amount of the Guaranteed Obligations and the amount of such
bid need not be paid by Holder but shall be credited against the Guaranteed
Obligations. The amount of the successful bid at any such sale shall be
conclusively deemed to be the fair market value of the Collateral and the
difference between such bid amount and the remaining balance of the Guaranteed
Obligations shall be conclusively deemed to be the amount of the Guaranteed
Obligations guaranteed under this Guaranty, notwithstanding any present or
future law or court decision or ruling that may have the effect of reducing the
amount of any deficiency claim to which Holder might otherwise be entitled but
for such bidding at any such sale.

3.   REPRESENTATIONS AND WARRANTIES. Subject to the limitations imposed by the
Existing Cases and certain insolvency proceedings in Bermuda and the resultant
fact that their activities are subject to approval of the United States
Bankruptcy Court and the Supreme Court of Bermuda, and the supervision and
oversight of the applicable joint provisional liquidators; PROVIDED, HOWEVER,
that the foregoing limitations shall cease to be applicable on and after the
earlier to occur of (i) the Plan Effective Date and (ii) October 31, 2002:

          3.1    ORGANIZATION, AUTHORITY AND QUALIFICATION OF THE GUARANTOR.
Guarantor is a company duly organized, validly existing and in good standing
under the laws of Bermuda and has all necessary power and authority to execute
and deliver this Guaranty, to carry out its obligations hereunder and to
consummate the transactions contemplated by this Guaranty. The execution and
delivery by Guarantor of this Guaranty, the performance by Guarantor of its
obligations hereunder and the consummation by Guarantor of the transactions
contemplated hereby have been duly authorized by all requisite corporate action
on the part of Guarantor. This Guaranty has been duly and validly executed and
delivered by Guarantor, and, assuming due authorization, execution and delivery
by Holder, this Guaranty constitutes the legal, valid and binding obligation of
Guarantor, enforceable against Guarantor in accordance with its terms.

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          3.2    NO CONFLICT. Guarantor's execution and delivery of this
Guaranty and the performance of its respective obligations hereunder, and the
consummation of the transactions contemplated hereby do not and will not (a)
violate, conflict with, or result in the breach of the Memorandum and Articles
of Association, bylaws or similar organizational documents of Guarantor, (b)
conflict with, or violate any Law or Governmental Order applicable to Guarantor,
or any of Guarantor's assets and properties, or (c) conflict with, result in any
violation or breach of, constitute a default (or event which with the giving of
notice or lapse of time, or both, would become a default) under, require any
consent under, or give to any Person any rights of termination, acceleration,
amendment, suspension, revocation or cancellation of, any contract, agreement,
undertaking or instrument to which Guarantor is a party or by which any of its
assets or properties are bound.

4.   COVENANTS; FURTHER ASSURANCES.

          (a)    [Intentionally omitted.]

          (b)    Guarantor agrees, upon the reasonable written request of
     Holder, to execute and deliver to Holder, from time to time, any additional
     instruments or documents reasonably considered necessary by Holder to cause
     this Guaranty to be, become, or remain valid and effective in accordance
     with its terms.

          (c)    FINANCIAL INFORMATION.

                 (i)   For so long as Guarantor is required to file
     financial statements and other periodic reports under the rules and
     regulations promulgated by the Securities and Exchange Commission (a
     "REPORTING COMPANY"), Guarantor shall furnish to Holder, within ten (10)
     days after transmission thereof, copies of all financial statements, proxy
     statements, reports and any other general written communications which the
     Guarantor sends to its members and copies of all registration statements
     and all regular, special or periodic reports which it files, or any of its
     officers or directors file with respect to the Guarantor, with the
     Securities and Exchange Commission or with any securities exchange on which
     any of its securities are then listed (if any), copies of all press
     releases and other statements made available generally by the Guarantor to
     the public concerning material developments in the Guarantor's and its
     Subsidiaries' Businesses;

                 (ii)  Commencing on the conclusion of the first fiscal
     quarter of Guarantor of which, and continuing for so long as, Guarantor is
     no longer a Reporting Company, Guarantor shall deliver to Holder as soon as
     available, and in any event within forty-five (45) days after the close of
     each fiscal quarter of Guarantor (or within ninety (90) days after the
     close of the quarter that is also the close of the fiscal year of
     Guarantor), financial information in a form substantially similar to that
     which Guarantor would be required to file with the Securities and Exchange
     Commission if it were still a Reporting Company; PROVIDED that the
     financial information provided for the first three fiscal quarters need
     not, in any case, be audited, PROVIDED further that such unaudited
     financial information presents fairly the consolidated financial position,
     results of operations and cash flows of the Guarantor and its Subsidiaries
     on a consolidated basis as of the respective dates thereof.

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                 (iii) Commencing on the conclusion of the first fiscal year
     of Guarantor of which, and continuing for so long as, Guarantor is no
     longer a Reporting Company, Guarantor shall deliver to Holder as soon as
     available, and in any event within ninety (90) days after the close of each
     fiscal year of the Guarantor, financial information in a form substantially
     similar to that which Guarantor would be required to file with the
     Securities and Exchange Commission if it were still a Reporting Company,
     PROVIDED that such audited financial statements shall be accompanied by:
     (i) an opinion of such accountants that does not contain any exceptions or
     qualifications and is to the effect that the financial statements described
     above fairly present the financial condition and the results of operations
     of the Guarantor and its Subsidiaries on a consolidated basis for the
     periods and as of the relevant dates thereof, and (ii) such accountants'
     management letter to the Guarantor relating to such audit report;

                 (iv)  Commencing on the conclusion of the first fiscal year
     of Guarantor of which, and continuing for so long as, Guarantor is no
     longer a Reporting Company, Guarantor shall present to Holder, at a
     location to be reasonably determined by Holder, the Guarantor's and its
     Subsidiaries' general review of the Business of Guarantor and its
     Subsidiaries. As part of such process, Guarantor shall, at Guarantor's sole
     expense, make such officers and employees as are reasonably requested by
     Holder available to discuss and answer questions regarding said Business.

     All of the financial information referred to in SUBSECTIONS (i) and (ii)
     above shall fairly present the financial condition and results of
     operations of the Guarantor and its Subsidiaries in all material respects
     as of the dates and for the periods stated therein, subject in the case of
     the unaudited financial statements to changes resulting from normal
     year-end auditing adjustments (none of which would, alone or in the
     aggregate, have a materially adverse effect on (a) the financial condition,
     operating results, prospects, assets, liabilities, operations, condition
     (financial or otherwise) or Business of the Guarantor and its Subsidiaries
     taken as a whole or (b) the ability of the Guarantor to satisfy the
     Guaranteed Obligations.

                 (v)   Guarantor shall deliver to Holder copies of any
     material financial information provided to the Guarantor's bondholders
     after the Effective Date pursuant to the Plan of Reorganization or
     otherwise within five (5) days after delivery thereof to such bondholders.

5.   PAYMENTS FREE AND CLEAR OF TAXES.

          If Guarantor shall be required by law to deduct any Taxes, other than
Excluded Taxes, from or in respect of any payment to Holder, (a) the amount of
such payment shall be increased as shall be necessary so that after Guarantor
has made all required deductions (including deductions applicable to additional
sums payable under this SECTION 5), Holder receives an amount equal to the sum
it would have received had no such deductions, other than deductions for
Excluded Taxes, been made, and (b) Guarantor shall make all such deductions and
pay the full amount deducted to the relevant taxation authority in accordance
with applicable law. Within thirty (30) days after the date of any payment of
Taxes, Guarantor shall furnish to Holder the original or a certified copy of a
receipt evidencing payment thereof. Guarantor shall jointly

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and severally indemnify and, within ten (10) days of demand therefore, pay
Holder for the full amount of Taxes (including any Taxes imposed by any
jurisdiction on amounts payable under this SECTION 5) paid by Holder, as
appropriate, and any liability (including penalties, interest and expenses)
arising therefrom or with respect thereto, whether or not such Taxes were
correctly or legally asserted.

6.   EFFECTIVE DATE.

          Notwithstanding anything herein to the contrary, Guarantor hereby
acknowledges and agrees that this Guaranty shall be effective for all purposes,
and shall have been deemed to have been continuously in effect, on and as of
May 16, 2002.

7.   OTHER TERMS.

          7.1    COMPLETE AGREEMENT; THIRD-PARTY BENEFICIARIES. This Guaranty,
together with the other Loan Documents, is intended by the parties as the final
expression of their agreement regarding the subject matter hereof and is a
complete and exclusive statement of the terms and conditions of such agreement.
There are no third-party beneficiaries of this Guaranty (other than successors
and assigns of Holder).

          7.2    ENGLISH LANGUAGE. Any translation of this Guaranty into another
language shall have no interpretive effect. All documents or notices to be
delivered pursuant to or in connection with this Guaranty shall be in the
English language, or, if any such document or notice is not in the English
language, accompanied by an English translation thereof, and the English
language version of any such document or notice shall control for purposes
hereof.

          7.3    HEADINGS. The headings in this Guaranty are for convenience of
reference only and are not part of the substance of this Guaranty.

          7.4    SEVERABILITY. Whenever possible, each provision of this
Guaranty shall be interpreted in such a manner to be effective and valid under
applicable law, but if any provision of this Guaranty shall be prohibited by or
made invalid under applicable law, such provision shall be ineffective to the
extent of such prohibition or invalidity, without invalidating the remainder of
such provision or the remaining provisions of this Guaranty.

          7.5    NOTICES. Every notice demand, request, consent, approval,
declaration or other communication hereunder shall be in writing and shall be
given or made (i) by delivery in person, (ii) by a reputable international
overnight courier service, or (iii) by telecopy to the respective parties at the
following addresses:

                 (a) If to Holder, at:

                     xxxx

                 (b) If to Guarantor, at:

                     FLAG TELECOM HOLDINGS LIMITED
                     c/o FLAG Telecom Group Limited

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                     Cedar House
                     41 Cedar Avenue
                     Hamilton HM12, Bermuda
                     Facsimile: (441) 296 0938
                     Attention: General Counsel

                     With a copy to (which shall not constitute notice):

                     FLAG Telecom Limited
                     9 South Street
                     London W1K 2XA, United Kingdom
                     Facsimile : +44 207 317 0898
                     Attention: General Counsel

or at such other address as may be substituted by notice given as herein
provided. The giving of any notice required hereunder may be waived in writing
by the party entitled to receive such notice. Every notice, demand, request,
consent, approval, declaration or other communication hereunder shall be deemed
to have been validly served, given or delivered (i) upon transmission, when sent
by telecopy or other similar facsimile transmission (with such telecopy or
facsimile promptly confirmed by delivery of a copy by personal delivery or
United States mail as otherwise provided in this SECTION 6.5), (ii) two (2)
Business Days after deposit with a reputable international overnight carrier
with all charges prepaid, or (iii) when delivered, if hand delivered.

          7.6    SUCCESSORS AND ASSIGNS. This Guaranty and all obligations of
Guarantor hereunder shall be binding upon the successors and assigns of
Guarantor (including a debtor-in-possession on behalf of Guarantor) and shall,
together with the rights and remedies of the Holder, inure to the benefit of
Holder, all future holders of any instrument evidencing any of the Guaranteed
Obligations and their respective successors and assigns; PROVIDED, HOWEVER, that
any such successor and assign shall be a "permitted assign" as defined in
Section 20 of the Secured Note. No sales of participations, other sales,
assignments, transfers or other dispositions of any agreement governing or
instrument evidencing the Guaranteed Obligations or any portion thereof or
interest therein shall in any manner affect the rights of Holder hereunder,
unless such sales, assignments, transfers or other dispositions were effected in
compliance with the provisions of the applicable Secured Note. Guarantor may
not, without the prior written consent of Holder, assign, sell, hypothecate or
otherwise transfer any interest in or obligation under this Guaranty except in
connection with the Plan.

          7.7    NO WAIVER; CUMULATIVE REMEDIES; AMENDMENTS. Holder shall not by
any act, delay, omission or otherwise be deemed to have waived any of its rights
or remedies hereunder, and no waiver shall be valid unless in writing, signed by
Holder and then only to the extent therein set forth. A waiver by Holder of any
right or remedy hereunder on any one occasion shall not be construed as a bar to
any right or remedy which Holder would otherwise have had on any future
occasion. No failure to exercise, nor any delay in exercising on the part of
Holder, any right, power or privilege hereunder, shall operate as a waiver
thereof, nor shall any single or partial exercise of any right, power or
privilege hereunder preclude any other or future exercise thereof or the
exercise of any other right, power or privilege. The rights and

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remedies hereunder provided are cumulative and may be exercised singly or
concurrently, and are not exclusive of any rights and remedies provided by law.
None of the terms or provisions of this Guaranty may be waived, altered,
modified, supplemented or amended except by an instrument in writing, duly
executed by Holder and Guarantor.

          7.8    TERMINATION. This Guaranty is a continuing guaranty and shall
remain in full force and effect until the Termination Date. Upon payment and
performance in full of the Guaranteed Obligations, Holder shall, at Guarantor's
sole expense, deliver to Guarantor such documents as Guarantor may reasonably
request to evidence such termination. The obligations of Holder contained in
this SECTION 6.8 shall survive the termination of this Guaranty and remain in
effect until Holder has complied in all material respects with all of such
obligations.

          7.9    COUNTERPARTS. This Guaranty may be executed in any number of
counterparts, each of which shall collectively and separately constitute one and
the same agreement.

          7.10   GOVERNING LAW. THIS GUARANTY AND ALL DISPUTES WITH RESPECT
HERETO SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE
STATE OF NEW YORK (OTHER THAN CHOICE OF LAW RULES THAT WOULD REQUIRE THE
APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION).

[THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK. SIGNATURE PAGE
FOLLOWS.]

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          IN WITNESS WHEREOF, the parties hereto have executed and delivered
this Guaranty as of the date first above written.


                              FLAG Telecom Holdings Limited


                              By:
                                  ----------------------------
                              Name: Kees van Ophem
                              Title: Assistant Secretary

                              xxxx


                              By:
                                  ----------------------------
                              Name:
                              Title:

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