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                                                     PRIVILEGED AND CONFIDENTIAL
                                                     STRICTLY CONFIDENTIAL

                                                  Exhibit 4.18

VIATEL HOLDING (BERMUDA) LIMITED
EBT CONTRIBUTION COVENANT

[NAME] DEPENDENT TRUST

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Contents

<TABLE>
<CAPTION>
CLAUSE                                                                               PAGE
<S>                                                                                  <C>
1.   DEFINITIONS..................................................................     1

2.   CONTRIBUTION TO THE EBT......................................................    17

3.   CALCULATION OF EQUITY VALUE AND TRANSACTION VALUE............................    24

4.   CESSATION OF EMPLOYMENT OF THE RELEVANT EMPLOYEE.............................    27

5.   PAYMENT OF PARTIAL LIQUIDITY CONTRIBUTIONS, CONTRIBUTIONS AND ADDITIONAL
     CONTRIBUTIONS WHERE CONSIDERATION IS PAYABLE OTHERWISE THAN IN CASH..........    28

6.   FULL LIQUIDITY EVENT.........................................................    30

7.   PARTIAL LIQUIDITY EVENT......................................................    30

8.   MULTIPLE LIQUIDITY EVENTS....................................................    31

9.   REORGANISATION...............................................................    32

10.  ADMINISTRATION...............................................................    32

11.  CONTRACTS (RIGHTS OF THIRD PARTIES) ACT 1999.................................    32

12.  GOVERNING LAW................................................................    32

13.  DISPUTE RESOLUTION...........................................................    33
</TABLE>

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                           EBT CONTRIBUTION COVENANT

This covenant is entered into on the 19 day of July 2005

BETWEEN:

(i)   VIATEL HOLDING (BERMUDA) LIMITED (Company number 31325) whose registered
      office is at Canon's Court, 22 Victoria Street, Hamilton HM12, Bermuda
      (the "COMPANY"); and

(ii)  EB TRUSTEES LIMITED whose registered office is at Whiteley Chambers, Don
      Street, St Helier, Jersey JE4 9WG as trustee of the VTL Employee Benefit
      Trust (the "TRUSTEE").

WHEREAS:

(A)   The Company wishes to covenant with the Trustee to make certain
      contributions to the VTL Employee Benefit Trust on the terms set out in
      this covenant.

(B)   The Trustee wishes to accept the contributions from the Company on the
      terms set out in this covenant.

1.    DEFINITIONS

1.1   In this covenant, except where the context otherwise requires, the words
      and expressions set out below shall bear the following respective
      meanings, namely:

        "ADDITIONAL                 the amount (if any) to be paid by the
        CONTRIBUTION(S)"            Company to the Trustee in relation to a Full
                                    Liquidity Event calculated in accordance
                                    with clause 2.6;

        "ADDITIONAL PERCENTAGE      the meaning given to it in clause 2.6;
        CONTRIBUTION"

        "AFFILIATE"                 in relation to a company any other company
                                    Controlling, Controlled by or under common
                                    Control with, that company and "AFFILIATED"
                                    shall be construed accordingly;

        "BOARD"                     the board of directors of the Company from
                                    time to time;

        "BUSINESS DAYS"             all days excluding Saturdays, Sundays and
                                    any day on which the London Stock Exchange

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                                    is closed for the transaction of business;

        "CAUSE"                     the meaning set out in clause 4.2.1;

        "CHANGE OF CONTROL"         (a)   with respect to the Company, the
                                          Company ceasing to be Controlled
                                          directly or indirectly by the
                                          Investors (it being understood that
                                          the transfer by one or more Investors
                                          of shares that leaves such Investor or
                                          other Investors (on a Fully Diluted
                                          Basis) with Control of the Company
                                          does not constitute a Change of
                                          Control of the Company); and

                                    (b)   with respect to a Subsidiary, such
                                          Subsidiary ceasing to be Controlled by
                                          the Company;

         "CLOSING DATE"             21 April 2004;

         "CONTRIBUTION"             the amount (if any) to be paid by the
                                    Company to the Trustee in relation to a Full
                                    Liquidity Event calculated in accordance
                                    with clauses 2.4 and 2.5;

        "CONTROL"                   in relation to a company:

                                    (a)   a person shall be taken to have
                                          control of a company if he exercises,
                                          or is able to exercise or is entitled
                                          to acquire, direct or indirect control
                                          over the company's affairs, and in
                                          particular, but without prejudice to
                                          the generality of the preceding words,
                                          if he possesses or is entitled to
                                          acquire:

                                          (i)   the greater part of the share
                                                capital or issued share capital
                                                of the company or of the voting
                                                power in the company; or

                                          (ii)  such part of the issued share

                                       2
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                                                capital of the company as would,
                                                if the whole of the income of
                                                the company were in fact
                                                distributed among the
                                                shareholders entitle him to
                                                receive the greater part of the
                                                amount so distributed; or

                                          (iii) such rights as would, in the
                                                event of the winding-up of the
                                                company or in any other
                                                circumstances, entitled him to
                                                receive the greater part of the
                                                assets of the company which
                                                would then be available for
                                                distribution among the
                                                shareholders;

                                    (b)   where two or more persons together
                                          satisfy any of the conditions of
                                          paragraph (a) above, they shall be
                                          taken to have control of the company;

                                    (c)   for the purposes of paragraph (a)
                                          above a person shall be treated as
                                          entitled to acquire anything which he
                                          is entitled to acquire at a future
                                          date, or will at a future date be
                                          entitled to acquire;

                                    (d)   for the purposes of paragraphs (a) and
                                          (b) above, there shall be attributed
                                          to any person any rights or powers of
                                          a nominee for him, that is to say, any
                                          rights or powers which another person
                                          possesses on his behalf or may be
                                          required to exercise on his direction
                                          or behalf; and

                                    (e)   for the purposes of paragraphs (a) and
                                          (b) above, there may also be
                                          attributed to any person all the
                                          rights and powers of any company or
                                          companies of which he has control,
                                          including those

                                       3
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                                          attributed to a company under
                                          paragraph (d) above,

                                    and "Controlled" shall be construed
                                    accordingly;

        "CONTROLLING SUBSIDIARY"    any Subsidiary of the Company which owns or
                                    controls all or substantially all of the
                                    assets of the Group;

        "DATE OF CESSATION"         the date on which a Relevant Employee ceases
                                    to be an employee of any member of the Group
                                    and does not immediately become an employee
                                    of another member of the Group;

        "DEPENDENT TRUST"           that part of the Trust Fund held on distinct
                                    trust for the Relevant Employee and his
                                    family;

        "DETERMINATION DATE"        the meaning given to it in clause 3.5 or
                                    3.6, as appropriate;

        "DILUTIVE ISSUE"            the issue of shares in the Company such that
                                    on a Fully Diluted Basis no one Investor or
                                    group of Investors collectively, holds a
                                    Significant Interest in the Company;

        "DISTRIBUTION"              following a conversion of the Viatel
                                    Convertible Notes (i) the pro rata
                                    distribution of any of the Company's assets
                                    in cash or otherwise to the holders of all
                                    of the common stock of the Company including
                                    (without limitation) by way of repurchase,
                                    redemption or cancellation of shares; or
                                    (ii) the non-pro rata purchase or redemption
                                    of common stock of the Company from one or
                                    more Investors (in a transaction not made
                                    available to all holders of common stock);

        "EBT"                       the VTL Employee Benefit Trust as
                                    established by the Company on -, - 2005;

        "EQUITY VALUE"              the meaning set out in clause 3.1;

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        "EXCHANGE RATE"             with respect to a particular currency on a
                                    particular date, the closing mid-point rate
                                    for the conversion of that currency into US
                                    Dollars on that date as set out in the
                                    London edition of the Financial Times first
                                    published after that date;

        "FLOTATION"                 the Company or a Controlling Subsidiary
                                    effecting a Listing (including the transfer
                                    of shares in the Company or a Controlling
                                    Subsidiary to a Listed Entity (other than a
                                    Qualified Transferee) and the amalgamation
                                    or merger of the Company with a Listed
                                    Entity or the subsidiary of a Listed Entity
                                    (in either cash not being a Qualified
                                    Transferee) in circumstances which do not
                                    constitute a Sale solely by virtue of the
                                    fact that following the transfer of such
                                    shares, amalgamation or transfer the
                                    Investors Control the Listed Entity (and if
                                    relevant, its subsidiary);

        "FULL LIQUIDITY EVENT"      the meaning set out in clause 6;

        "FULLY DILUTED BASIS"       means that all securities of an entity
                                    convertible into, or exchangeable or
                                    exercisable for, ordinary shares of that
                                    entity have been so converted, exchanged or
                                    exercised and such ordinary shares have been
                                    issued;

        "FURTHER CONTRIBUTION(S)"   any payment made or to be made by the
                                    Company to the Trustee, in accordance with
                                    clause 2.8;

        "GOOD REASON"               the meaning set out in clause 4.2.2;

        "GROUP"                     the Company and any Subsidiary of the
                                    Company or, where the context permits, any
                                    one or more of them, and references to
                                    "member of the Group" shall be construed
                                    accordingly;

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        "INVESTMENT AGREEMENT"      the investment and note purchase agreement
                                    entered into by the Company and others on 21
                                    April 2004;

        "INVESTORS"                 the Purchasers (as such term is defined in
                                    the Investment Agreement);

        "LIQUIDATION"               in relation to a company, the entry of a
                                    winding up order by a court having
                                    jurisdiction or the passing of a resolution
                                    by the shareholders of the company, for the
                                    solvent winding up of the company;

        "LIQUID CONSIDERATION"      cash equivalents and shares of a Listed
                                    Entity which (a) are not subject to any
                                    restrictions on sale and (b) have an average
                                    monthly trading volume at the Determination
                                    Date sufficient so that in the view of the
                                    Board, the Investors are likely to be able
                                    to dispose of all such shares received as
                                    consideration or otherwise in connection
                                    with a Full Liquidity Event or Partial
                                    Liquidity Event without adversely affecting
                                    the average trading price thereof;

        "LISTED ENTITY"             any company which has effected a Listing and
                                    continues to be Listed;

        "LISTING"                   in relation to a company:

                                    (a)   a public offering for cash of an
                                          amount of that company's shares equal
                                          to at least 20% of the issued share
                                          capital of that company where,
                                          following such offering, the shares of
                                          the company are registered with the US
                                          Securities and Exchange Commission
                                          pursuant to the Securities and
                                          Exchange Act 1934 or traded on a US
                                          securities exchange or in the National
                                          Association of Securities Dealers
                                          Automated Quotation System (NASDAQ);
                                          or

                                       6
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                                    (b)   the admission of any part of the share
                                          capital of that company to listing on
                                          the Official List of the UK Listing
                                          Authority and to trading on the London
                                          Stock Exchange plc's market for listed
                                          securities; or

                                    (c)   the admission of any part of the share
                                          capital of that company to trading on
                                          any other securities exchange;

                                    in any case, following a resolution of the
                                    board of the relevant company, to pursue
                                    such a Listing, and "LISTED" shall be
                                    construed accordingly;

        "MATERIAL ASSET"            on any date, any asset(s) or undertaking of
                                    a member of the Group where:

                                    (a)   the amount payable on the transfer of
                                          such asset(s) or undertaking exceeds
                                          US$10 million; or

                                    (b)   such asset(s) or undertaking represent
                                          10% or more of the net assets of the
                                          entire Group (as shown in the audited
                                          consolidated accounts of the Group
                                          last published prior to that date); or

                                    (c)   the board of the Company determines
                                          that such assets or undertaking should
                                          otherwise be classed as material in
                                          the context of the business of the
                                          Group as a whole for the purposes of
                                          this covenant;

                                    and the following shall in any event (but
                                    without limitation) constitute `Material
                                    Assets' notwithstanding and without
                                    prejudice to paragraphs (a) to (c) above:

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                                    (i)   the asset(s) and undertaking
                                          comprising the Group's
                                          telecommunications network in any
                                          single country in Europe (as of the
                                          Closing Date), including (without
                                          limitation) ducts, cables, rights of
                                          way, easements, indefeasible rights of
                                          use, points of presence, co-location
                                          facilities and repeater stations;

                                    (ii)  the asset(s) and undertaking
                                          comprising the Group's commercial
                                          operations in the UK or Switzerland or
                                          in the whole of Europe including
                                          (without limitation) contracts for the
                                          supply of communications services;

        "MATERIAL SUBSIDIARY"       any Subsidiary of the Company which owns a
                                    Material Asset;

        "MAXIMUM ADDITIONAL         the maximum percentage of Equity Value used
        PERCENTAGE CONTRIBUTION"    to calculate the amount of any Additional
                                    Contribution due to the EBT pursuant to
                                    clause 2.6;

        "MAXIMUM PERCENTAGE         the maximum percentage of Equity Value used
        CONTRIBUTION"               to calculate the amount of any Contribution
                                    due to the EBT pursuant to clause 2.4;

        "PARTIAL LIQUIDITY          the amount (if any) paid or to be paid by
        CONTRIBUTION"               the Company to the Trustee in relation to a
                                    Partial Liquidity Event calculated in
                                    accordance with clause 2.7;

        "PARTIAL LIQUIDITY EVENT"   the meaning set out in clause 7;

        "PAYMENT DUE DATE"          the tenth Business Day following a
                                    Determination Date;

                                       8
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        "POST-FLOTATION TRANSFER"   following a Flotation of the Company or a
                                    Controlling Subsidiary, a transfer by the
                                    Investors (or any one or more of them) of
                                    common stock in the Company or a transfer by
                                    the Company of shares in a Controlling
                                    Subsidiary, in either event to a person or
                                    to an entity that is not a Qualified
                                    Transferee the proceeds of which are either:

                                    (a)   together, equal to or in excess of
                                          $10 million; or

                                    (b)   when aggregated with the proceeds of
                                          all previous transfers (to persons or
                                          entities that are not Qualified
                                          Transferees) of common stock of the
                                          Company or shares in the Controlling
                                          Subsidiary made by any of the
                                          Investors or the Company (as
                                          appropriate) following such Flotation,
                                          equal to or in excess of $10 million;

                                    and so that (for the avoidance of doubt) any
                                    transfer of common stock by any Investor or
                                    shares by the Company (as appropriate)
                                    following a Flotation shall constitute a
                                    Post-Flotation Transfer if the aggregate
                                    proceeds of all previous transfers of common
                                    stock of the Company or shares of a
                                    Controlling Subsidiary (as appropriate) (to
                                    persons or entities that are not Qualified
                                    Transferees) by that Investor and/or any
                                    other Investor, or the Company (as
                                    appropriate) is equal to or in excess of $10
                                    million;

        "QUALIFIED TRANSFEREE"      any Investor or any Affiliate of any
                                    Investor, but excluding any such Affiliate
                                    that is primarily involved in a line of
                                    business that is substantially different
                                    from the lines of business primarily engaged
                                    in by the Investor (and any parent entity of
                                    the Investor on a

                                       9
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                                    consolidated basis) with whom such Affiliate
                                    is Affiliated, it being understood that for
                                    this purpose the business of holding
                                    investments shall be deemed to be a business
                                    in which each Investor is primarily engaged;

        "RELEVANT DATE"             (a)   in relation to a Full Liquidity Event:

                                          (i)   by way of a Sale of the Company,
                                                the date of the transfer of the
                                                shares(s) which results in the
                                                occurrence of a Sale;

                                          (ii)  by way of a Liquidation of the
                                                Company, the date following
                                                commencement of the Liquidation
                                                on which the liquidator
                                                determines that a distribution
                                                of surplus assets of the Company
                                                can be made (without taking into
                                                account the provisions of this
                                                covenant);

                                    (b)   in relation to a Partial Liquidity
                                          Event:

                                          (i)   by way of the transfer (to a
                                                person or entity that is not a
                                                Qualified Transferee) of a
                                                Material Asset followed by a
                                                Distribution of proceeds, the
                                                date of the Distribution of the
                                                proceeds in connection with such
                                                transfer;

                                          (ii)  by way of the Liquidation of a
                                                Material Subsidiary followed by
                                                a Distribution of the proceeds
                                                of the Liquidation, the date of
                                                Distribution of such proceeds in
                                                connection with such
                                                Liquidation;

                                          (iii) by way of a Post-Flotation
                                                Transfer of shares in a
                                                Controlling Subsidiary (to a
                                                person or entity

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                                                that is not a Qualified
                                                Transferee) followed by a
                                                Distribution of the proceeds of
                                                such transfer, the date of the
                                                Distribution of the proceeds in
                                                connection with such
                                                Post-Flotation Transfer;

                                          (iv)  by way of a Tag-Along
                                                Transaction, the date of the
                                                transfer of the relevant shares;

                                          (v)   by way of a Post-Flotation
                                                Transfer of shares in the
                                                Company, the date of the
                                                transfer of the relevant shares;

                                          (vi)  by way of an amalgamation or
                                                merger of the Company under
                                                clause 7.1.5, the date on which
                                                the amalgamation or merger takes
                                                place;

                                    and, for the avoidance of doubt, more than
                                    one Relevant Date can occur in relation to a
                                    Partial Liquidity Event in accordance with
                                    the provisions of clause 3.4;

        "RELEVANT EMPLOYEE"         [NAME];

        "REMUNERATION COMMITTEE"    the remuneration committee of the board of
                                    Directors of the Company as duly authorised
                                    from time to time;

        "REORGANISATION"            (a)   any amalgamation or merger for
                                          internal reorganisation purposes of
                                          the Company with another body
                                          corporate (other than where the
                                          Company is the principal surviving or
                                          remaining body corporate);

                                    (b)   any reorganisation of the Company as
                                          a result of which all or part of the

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                                          business of the Group becomes
                                          Controlled by a new company which is
                                          not currently a member of the Group,
                                          but which is itself Controlled by the
                                          Investors (whether alone or together
                                          with any other persons) in the same or
                                          substantially the same proportions as
                                          the Investors hold or would hold
                                          shares in the Company, on a Fully
                                          Diluted Basis, immediately prior to
                                          the reorganisation; or

                                    (c)   the acquisition (other than by way
                                          of a subscription for shares) by a
                                          company (including, without
                                          limitation, a Listed Entity) of shares
                                          in the Company or an amalgamation or
                                          merger of the Company with another
                                          company in circumstances which do not
                                          constitute a Sale by virtue of the
                                          fact that following the transfer,
                                          merger or amalgamation, given the
                                          shareholding structure of the
                                          acquiring company or surviving entity,
                                          either there has been no effective
                                          Change of Control of the Company or
                                          the Investors retain a Significant
                                          Interest in the acquiring company, or
                                          surviving entity; or

                                    (d)   a Dilutive Issue,

                                    but notwithstanding the foregoing, no
                                    amalgamation, reorganisation, acquisition,
                                    issue or other transaction that constitutes
                                    a Reorganisation shall, unless the Board
                                    determine otherwise in accordance with
                                    clause 8, also constitute a Partial
                                    Liquidity Event or a Full Liquidity Event
                                    and no amalgamation, reorganisation,
                                    acquisition, issue or other transaction that
                                    constitutes a Partial Liquidity Event or a
                                    Full Liquidity Event

                                       12
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                                    shall, unless the Board determines otherwise
                                    in accordance with clause 8, also constitute
                                    a Reorganisation;

        "SALE"                      in relation to the Company, the transfer by
                                    one or more Investors of shares by way of
                                    Tag-Along Transaction or a Post-Flotation
                                    Transfer or the amalgamation or merger of
                                    the Company with another company, or other
                                    sale of shares following a Tag-Along
                                    Transaction or amalgamation or merger (in
                                    one transaction or as a series of related
                                    transactions) as a result of which:

                                    (a)   there is a Change of Control of the
                                          Company following which, no one
                                          Investor, or group of Investors
                                          collectively, holds a Significant
                                          Interest in the Company (or, following
                                          an amalgamation or merger, in the
                                          surviving entity); or

                                    (b)   (in the event of a transfer of shares
                                          following the previous occurrence of a
                                          Change of Control of the Company which
                                          does not constitute a Sale under
                                          paragraph (a) above) no one Investor,
                                          or group of Investors collectively,
                                          holds a Significant Interest in the
                                          Company (or, following an amalgamation
                                          or merger, in the surviving entity);

        "SERVICE AGREEMENT"         the service agreement between the Relevant
                                    Employee and [the Company][VTL UK Limited]
                                    dated [date];

        "SHAREHOLDER"               in relation to the Company, the holders of
                                    shares in the Company;

        "SHARES"                    any shares or common stock in a company and
                                    any right to acquire or convert any

                                       13
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                                    security into, shares or common stock in a
                                    company;

        "SHAREHOLDERS' AGREEMENT"   the shareholders' agreement entered into by
                                    the Company and others on 21 April 2004;

        "SIDE LETTER"               the letter of even date herewith between the
                                    Company and the Trustee;

        "SIGNIFICANT INTEREST"      in relation to a company, the holding of or
                                    the ability to be able to exercise or to
                                    acquire direct or indirect control over,
                                    more than 20% of the voting rights attaching
                                    to that company's shares on a Fully Diluted
                                    Basis;

        "SUBSIDIARY"                a subsidiary undertaking as defined in
                                    section 258 of the Companies Act 1985;

        "TAG-ALONG TRANSACTION"     a sale of shares to a person or entity that
                                    is not a Qualified Transferee that triggered
                                    (or would have been capable of triggering)
                                    any of the "tag-along" rights as set out in
                                    Section 3.4(a) or 3.4(d) of the
                                    Shareholders' Agreement;

        "TAXES ACT"                 the Income and Corporation Taxes Act 1988;

        "TRANSACTION VALUE"         the meaning set out in clause 3.2;

        "TRANSACTION VALUE          at any date, the aggregate of the
        THRESHOLD"                  Transaction Values of all Partial Liquidity
                                    Events with Relevant Dates on or prior to
                                    such date being equal to or exceeding $100
                                    million;

        "TRANSFER"                  (in relation to any asset) the direct or
                                    indirect transfer of that asset (and for the
                                    avoidance of doubt, but without limitation,
                                    reference to an asset shall include a share)
                                    whether by way of sale, gift, holding on
                                    trust and whether at law or in equity,
                                    including in the case of a share, an
                                    agreement to exercise generally the voting
                                    rights attaching to that share at the
                                    direction of any third party, but excluding
                                    (a) the grant of a

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                                    revocable proxy with regard to any share;
                                    and (b) the grant, release or exercise of
                                    any security granted over any asset for the
                                    purposes of securing a monetary obligation
                                    (it being understood that a Flotation cannot
                                    of itself be a "transfer" and the transfer
                                    of shares in an entity shall only constitute
                                    a "transfer" of that entity (as distinct
                                    from the shares) if such transfer of shares
                                    results in a Change of Control of that
                                    entity);

        "TRIGGER DATE"              (a)   in relation to a Full Liquidity Event:

                                    (i)   by way of a Sale of the Company, the
                                          date of the transfer of the share(s)
                                          which result in the occurrence of a
                                          Sale;

                                    (ii)  by way of a Liquidation of the
                                          Company, the date on which the
                                          resolution to wind the Company up is
                                          passed by the shareholders or the date
                                          on which an order to wind up the
                                          Company is granted, whichever is the
                                          earlier; and

                                    (b)   in relation to a Partial Liquidity
                                          Event:

                                    (i)   by way of the transfer of a Material
                                          Asset, the date of disposal of such
                                          asset;

                                    (ii)  by way of the Liquidation of a
                                          Material Subsidiary the date on which
                                          the resolution to wind up the company
                                          is passed by the shareholders or the
                                          date on which an order to wind up the
                                          company is granted, whichever is the
                                          earlier;

                                    (iii) by way of a Post-Flotation Transfer of
                                          shares in a Controlling Subsidiary the
                                          date of the transfer of such shares;

                                       15
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                                    (iv)  by way of a Tag-along Transaction, the
                                          date of the relevant transfer of
                                          shares;

                                    (v)   by way of a Post-Flotation Transfer of
                                          shares in the Company, the date of the
                                          relevant transfer of shares; and

                                    (vi)  by way of an amalgamation or merger of
                                          the Company under clause 7.1.5, the
                                          date on which the amalgamation or
                                          merger takes place;

        "TRUST FUND"                the meaning given to it under the EBT;

        "VIATEL CONVERTIBLE NOTES"  the Viatel Holding (Bermuda) Limited 8%
                                    Convertible Senior Secured Notes due 2014;
                                    and

        "WAIVER"                    the form of Waiver set forth in Annex A
                                    hereto.

1.2   In this covenant:

        1.2.1 any reference to a statutory or regulatory provision shall be
              deemed to include that provision as it may from time to time be
              amended or re-enacted, and, wherever the context so admits or
              requires, the singular shall include the plural and vice versa and
              the masculine shall include the feminine;

        1.2.2 "PARENT UNDERTAKING" shall have the meaning ascribed to it in
              section 258 of the Companies Act 1985;

        1.2.3 reference to any English legal term for any action, remedy, method
              of judicial proceeding, legal document, legal status, court,
              official or any legal concept or thing includes, in respect of any
              jurisdiction other than England, a reference to whatever most
              closely approximates in that jurisdiction to the relevant English
              legal term;

        1.2.4 any phrase introduced by the terms "INCLUDE", "INCLUDING", "IN
              PARTICULAR" or any similar expression shall be construed as
              illustrative and shall not limit the sense of the words preceding
              those terms; and

        1.2.5 a reference to a company shall be to a body corporate, whenever
              incorporated.

1.3   Any reference in this covenant to a sum expressed in $ (US Dollars), in
      the context of any sum denominated in any other currency (such as for
      example, but without limitation, a

                                       16
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      reference to the proceeds of sale of shares exceeding a sum in US Dollars)
      shall be converted into US Dollars at the Exchange Rate on the relevant
      date. In the case of any value required to be converted into US Dollars
      for the purposes of calculating the Transaction Value or Equity Value or
      the amount of a Partial Liquidity Contribution or Contribution or
      Additional Contribution, if appropriate, due following a Partial Liquidity
      Event or a Full Liquidity Event, the relevant date shall be the Relevant
      Date in relation to such Partial Liquidity Event or Full Liquidity Event.

2.    CONTRIBUTION TO THE EBT

2.1   The Company hereby undertakes, subject to the provisions of clause 5, that
      on or prior to any Payment Due Date, it will make a Partial Liquidity
      Contribution (if the Payment Due Date relates to a Partial Liquidity
      Event) or a Contribution and, if applicable, an Additional Contribution
      (if the Payment Due Date relates to a Full Liquidity Event) in cash to the
      Trustee, as trustee of the EBT, calculated in accordance with the terms of
      this covenant. The Trustee hereby declares itself trustee of the benefit
      of this covenant to hold the same for the benefit of the persons who are
      the beneficiaries under the terms of the EBT, in accordance with the terms
      of the EBT. Notwithstanding any other term of this covenant:

      2.1.1 if neither a Partial Liquidity Event nor a Full Liquidity Event has
            occurred by 21 April 2014 no Partial Liquidity Contribution or
            Contribution or Additional Contribution will be made to the Trustee
            and in this event this covenant shall terminate on 21 April 2014;

      2.1.2 no Partial Liquidity Contribution or Contribution or Additional
            Contribution shall be made with respect to any transaction or event
            with respect to which the Relevant Date is after 21 April 2014; and

      2.1.3 no Partial Liquidity Contribution or Contribution or Additional
            Contribution will be made with respect to any Relevant Employee who
            has not executed and delivered the Waiver on or prior to 10 Business
            Days after the date of this covenant.

2.2   Notwithstanding anything to the contrary in this covenant, the obligations
      of the Company under clause 2.1 above shall be alternative to and not
      additional to the obligations of [the Company] [VTL UK Limited] ("EXISTING
      OBLIGATIONS") under clause [ ] of the Service Agreement. If the Existing
      Obligations remain in full force and effect, the Company shall not be
      liable to make any payment under clause 2.1 above.

2.3   The Trustee agrees that any Partial Liquidity Contribution, Contribution
      (and, if applicable, any Additional Contribution) made by the Company
      under this covenant will

                                       17
<PAGE>

      immediately be transferred by the Trustee to the [NAME] Dependent Trust
      and will be held by the Trustee in accordance with the terms of that
      trust.

2.4   In relation to a Full Liquidity Event the amount of the Contribution will
      depend on:

      2.4.1 the Equity Value at the Relevant Date of the Full Liquidity Event
            and will be calculated as a percentage of such Equity Value as
            follows:

<TABLE>
<CAPTION>
EQUITY VALUE US$                 MAXIMUM PERCENTAGE CONTRIBUTION
---------------------            -------------------------------
<S>                              <C>
Less than 100 million                           0
100 million
350 million or more
</TABLE>

            and the Maximum Percentage Contribution used to calculate the amount
            of Contribution due where the Equity Value is greater than $US100
            million, but less than US$350 million, shall be pro rated on a
            straight line basis; and

      2.4.2 whether the Relevant Employee has ceased to be an employee of a
            member of the Group (and has not immediately become an employee of
            another member of the Group) prior to the Trigger Date relating to
            the Full Liquidity Event, in which case, only a proportion of the
            Contribution otherwise due will be deemed to have vested, as
            follows:

<TABLE>
<CAPTION>
                                                      AMOUNT OF MAXIMUM
                                                   PERCENTAGE CONTRIBUTION
TRANCHE               DATE OF CESSATION                  WHICH VESTS
-------        ------------------------------      -----------------------
<C>            <C>                                 <C>
1              prior to 21 April 2005                         1/3
2              21 April 2005 to 20 April 2006                 2/3
3              on or after 21 April 2006                      3/3
</TABLE>

            SAVE that:

            (a)   in the event of the cessation of employment of the Relevant
                  Employee due to one of the reasons set out in clause 4.1, the
                  vesting of the entitlement to a Contribution shall be
                  accelerated as set out in clause 4.1; and

            (b)   in the event that there has been a Change of Control of the
                  Company on or prior to the Date of Cessation the entitlement
                  to a Contribution shall be

                                       18
<PAGE>

                  accelerated in full so that the whole amount of the
                  Contribution (if any) shall be payable on any Full Liquidity
                  Event with a Trigger Date on or following such Date of
                  Cessation; and

      2.4.3 whether any Partial Liquidity Contributions have previously been
            made in connection with a Partial Liquidity Event or any other
            Further Contributions have been made under clause 2.8 (other than
            Further Contributions made under clause 2.8 which are not linked to
            a Partial Liquidity Event) and the Trustee has exercised its
            discretion and passed such payments to the Dependant Trust, in which
            case there shall be deducted from the Contribution due in relation
            to the Full Liquidity Event, the aggregate of all previous Partial
            Liquidity Contributions (if any) and any such Further Contributions
            made under clause 2.8. For the avoidance of doubt, if a payment has
            been made to the Trustee pursuant to clause 2.8 in connection with a
            Partial Liquidity Event, but at the Relevant Date of the Full
            Liquidity Event, such payment has not been transferred in its
            entirety to the Dependent Trust then payment shall, for the purposes
            of this clause and clause 2.5, be deemed to have been made into each
            dependent trust held by the Trustee for the benefit of employees of
            the Company and their families in force at that time, in accordance
            with any letter of wishes given by the Company to the Trustee in
            respect of such payment and, in the absence of any such letter, into
            each such dependent trust pro rata based on prior contributions.

2.5   For the avoidance of doubt, the Relevant Employee does not need to be an
      employee of any member of the Group at the Relevant Date, the
      Determination Date or the Payment Due Date, in relation to any Full
      Liquidity Event in order for the full amount of any Contribution to become
      payable pursuant to this covenant, provided that either he was an employee
      of any member of the Group at the Trigger Date relating to such Full
      Liquidity Event or, if he has ceased to be an employee at the Trigger
      Date, a Change of Control had occurred on or prior to the Date of
      Cessation. If the Relevant Employee has ceased to be an employee of a
      member of the Group (and does not immediately become an employee of
      another member of the Group) prior to the Trigger Date in relation to a
      Full Liquidity Event (and no Change of Control had occurred prior to the
      Date of Cessation), the amount of the Contribution to be made after the
      Date of Cessation in relation to such Full Liquidity Event, will be
      calculated as follows:

      [(A x B) x E] - C

      where:

      A  =  the Maximum Percentage Contribution applicable to that Full
            Liquidity Event, in accordance with clause 2.4.1;

                                       19
<PAGE>

      B  =  the fraction of the Maximum Percentage Contribution which has
            vested in accordance with clause 2.4.2 at the Date of Cessation
            (subject to any acceleration pursuant to clause 2.4.2);

      C  =  the aggregate of all previous Partial Liquidity Contributions (if
            any) made to the Trustee in respect of such Relevant Employee prior
            to the Relevant Date of that Full Liquidity Event, as a result of
            any previous Partial Liquidity Events and any other Further
            Contributions made under clause 2.8 (other than Further
            Contributions not linked to a Partial Liquidity Event) and in
            respect of which the Trustee has exercised its discretion to
            transfer such payment into the Dependent Trust (or is deemed to have
            done so pursuant to clause 2.4.3); and

      E  =  the Equity Value applicable to that Full Liquidity Event.

2.6   Additional Contributions

      2.6.1 In addition, the Company may, following the first anniversary of the
            Closing Date and any subsequent anniversary of the Closing Date, as
            appropriate at the discretion of the Remuneration Committee (after
            recommendations by the Chief Executive Officer of the Company) and
            dependent upon the Relevant Employee having achieved objectives and
            performance standards during the 12 months from the Closing Date
            and/or during any subsequent 12 month period for the duration of the
            Service Agreement, determine that, on a Full Liquidity Event, an
            Additional Contribution will be made. Any such Additional
            Contribution will be calculated as a percentage of the Equity Value
            at the Relevant Date of a Full Liquidity Event. The Board shall send
            a written notice to the Trustee within 10 Business Days of such a
            determination informing the Trustee that an award under this clause
            2.6.1 has been made and the applicable percentage range (within the
            maximum ranges set out below) for the purposes of calculating any
            Additional Contribution due ("ADDITIONAL PERCENTAGE Contribution").
            The total of all awards of an Additional Percentage Contribution
            under this clause 2.6.1 shall be within the following maximum
            aggregate Additional Percentage Ranges:

<TABLE>
<CAPTION>
                                           MAXIMUM ADDITIONAL PERCENTAGE
EQUITY VALUE US$                                   CONTRIBUTION
---------------------                      -----------------------------
<S>                                        <C>
Less than 100 million                                    0
100 million
350 million or more
</TABLE>

                                       20
<PAGE>

            and the Maximum Additional Percentage Contribution and/or the
            Additional Percentage Contribution used to calculate the amount of
            Additional Contribution due where the Equity Value is greater than
            US$100 million but less than US$350 million, shall be pro rated on a
            straight line basis. Additional Percentage Contributions where
            awarded, shall be fully vested on the date on which the Board
            determines that an Additional Percentage Contribution shall be made.

      2.6.2 For the avoidance of doubt, the Relevant Employee does not need to
            be an employee of any member of the Group at the Relevant Date, the
            Determination Date or the Payment Due Date in relation to any Full
            Liquidity Event in order for the amount of any Additional
            Contribution awarded under this paragraph 2.6 to become payable,
            provided that he was an employee of any member of the Group at the
            Trigger Date relating to such Full Liquidity Event or, if he has
            ceased to be an employee at the Trigger Date, a Change of Control of
            the Company had occurred on/or prior to the Date of Cessation.

2.7   In relation to a Partial Liquidity Event:

      2.7.1 the amount of the Partial Liquidity Contribution shall depend on
            whether, at the Relevant Date in relation to that Partial Liquidity
            Event, the Transaction Value Threshold has been met or exceeded, in
            which case the Partial Liquidity Contribution shall be calculated as
            follows:

            {[X x (Y + Z)] x TV} - PC

            where:

            X = 60% in relation to all Partial Liquidity Events where the
            aggregate of the Transaction Value relating to that Partial
            Liquidity Event and the Transaction Values of all previous Partial
            Liquidity Events does not exceed US$200 million, and 100% in
            relation to all Partial Liquidity Events where the aggregate of the
            Transaction Value relating to that Partial Liquidity Event and the
            Transaction Values of all previous Partial Liquidity Events exceeds
            US$200 million;

            Y = in relation to a Partial Liquidity Event, the Maximum Percentage
            Contribution payable in relation to that Partial Liquidity Event
            pursuant to the table set out in clause 2.4.1 if "TV" (as defined
            below) were substituted for "Equity Value" and "Partial Liquidity
            Event" were substituted for "Full Liquidity Event" in such clause;

            Z = in relation to a Partial Liquidity Event, the aggregate of any
            Additional Percentage Contributions (if any have been awarded by the
            Board pursuant to

                                       21
<PAGE>

            clause 2.6.1) payable in relation to a Partial Liquidity Event
            pursuant to any awards made by the Board under clause 2.6.1, (for
            the avoidance of doubt subject to the Maximum Additional Percentage
            Contribution set out in the table in clause 2.6.1) as if "TV" (as
            defined below) were substituted for "Equity Value" and "Partial
            Liquidity Event" were substituted for "Full Liquidity Event" in
            clause 2.6.1;

            TV = in relation to any Partial Liquidity Event in respect of which
            the Transaction Value Threshold has been met or exceeded, the
            aggregate of the Transaction Value relating to that Partial
            Liquidity Event and the Transaction Values of all previous Partial
            Liquidity Events; and

            PC = in relation to a Partial Liquidity Event, the aggregate amount
            of all previous Partial Liquidity Contributions made to the Trustee
            pursuant to this clause 2.7 in respect of the Relevant Employee
            prior to the Relevant Date of that Partial Liquidity Event;

            and so that, for the avoidance of doubt, once the Transaction Value
            Threshold has been met or exceeded, a Partial Liquidity Contribution
            shall (subject to the other terms of this covenant) be payable in
            respect of all subsequent Partial Liquidity Events;

      2.7.2 if a Partial Liquidity Contribution is required to be made under
            clause 2.7.1, such Partial Liquidity Contribution shall be made
            whether or not the Relevant Employee has ceased to be an employee of
            any member of the Group at the Relevant Date or the Determination
            Date or the Payment Due Date so long as the Relevant Employee was
            employed by a member of the Group at the Trigger Date relating to
            that Partial Liquidity Event (and, if no Partial Liquidity
            Contributions have previously been made, at the Trigger Date
            relating to the most recent Partial Liquidity Event). Subject to the
            following provisions of this clause 2.7.2, no Partial Liquidity
            Contribution shall be made with respect to any Partial Liquidity
            Event, the Trigger Date of which occurs following the Date of
            Cessation of the Relevant Employee's employment. Notwithstanding the
            foregoing provisions of this clause 2.7.2, in the event that,
            pursuant to clause 3.4, there is more than one Relevant Date, more
            than one Determination Date, and more than one Payment Due Date in
            relation to any Partial Liquidity Event, then provided that the
            Relevant Employee was employed by a member of the Group at the
            Trigger Date relating to that Partial Liquidity Event he shall be
            entitled to receive all Partial Liquidity Contributions which become
            payable following any number of subsequent Relevant Dates relating
            to that same Partial Liquidity Event, except that such Relevant
            Employee shall not be entitled

                                       22
<PAGE>

            to receive payments with respect to any Partial Liquidity Event
            following the Relevant Date of a Full Liquidity Event.

2.8   In addition, the Company may, at the discretion of the Remuneration
      Committee (after recommendations by the Chief Executive Officer of the
      Company), make Further Contributions to the Trustee in such amounts as the
      Remuneration Committee, in its sole discretion, determines, such payments
      to be held on the terms of the EBT.

2.9   Side Letter Cap

      Notwithstanding anything to the contrary in this covenant:

      2.9.1 on any Partial Liquidity Event, the Company shall be under no
            obligation to make any payment in excess of the Partial Liquidity
            Contribution due under clause 2.7.1;

      2.9.2 on a Full Liquidity Event, the Company shall be under no obligation
            to make any payment in excess of the aggregate of the Maximum
            Percentage Contribution due under clause 2.4.1 and the Maximum
            Additional Percentage Contribution (if any) due under clause 2.6,
            minus, the amount of all previous Partial Liquidity Contributions;
            and:

      2.9.3 the Company shall not be under any obligation to make any payment to
            the Trustee under this covenant or otherwise to the extent that such
            payment together with any other payments made to the Trustee under
            or in connection with the EBT in relation to any Partial Liquidity
            Event or Full Liquidity Event would cause a violation of the
            provisions of paragraph 5 of the Side Letter ("SIDE LETTER CAP");

      provided that:

      (a)   this clause 2.9 shall not prevent the Company in its discretion from
            making Further Contributions pursuant to clause 2.8 in relation to
            any Full Liquidity Event or Partial Liquidity Event as long as the
            Side Letter Cap is not exceeded or from making Further Contributions
            pursuant to clause 2.8 otherwise than in connection with any Full
            Liquidity Event or Partial Liquidity Event, irrespective of the Side
            Letter Cap; and

      (b)   nothing in this covenant shall require the Trustee to repay any
            amounts previously received by it in respect of any Partial
            Liquidity Event occurring prior to any other Partial Liquidity Event
            or Full Liquidity Event.

                                       23
<PAGE>

3.    CALCULATION OF EQUITY VALUE AND TRANSACTION VALUE

3.1   For the purposes of this covenant and in relation to a Full Liquidity
      Event, "EQUITY VALUE" shall have the meaning as determined pursuant to and
      in accordance with Schedule 3 to the Investment Agreement (for the
      avoidance of doubt excluding the value of any shares no longer in issue
      due to their having been repurchased, redeemed or otherwise ceasing to be
      outstanding following the Closing Date), as adjusted to include the value
      of all Distributions made to shareholders since the Closing Date but prior
      to the Relevant Date in relation to such Full Liquidity Event, and subject
      to any further adjustments deemed to be equitable and necessary, in the
      complete discretion of the Board, in order to give effect to the
      intentions of all parties pursuant to the principles set out in this
      covenant (provided that such valuation and adjustments do not result in
      double counting). For the purposes of calculating Equity Value, the value
      of any non-cash Distribution or consideration received shall be calculated
      in accordance with clause 3.3.

3.2   For the purposes of this covenant the following terms shall have the
      following meanings:

      "TRANSACTION VALUE" shall mean the following, it being understood that in
      any case in which there is any ambiguity with respect to the proper
      determination of Transaction Value, it shall be in the discretion of the
      Board to determine the Transaction Value in a manner that operates fairly
      as between the Company and the Trustee:

      (a)   with respect to a Partial Liquidity Event described in clauses 7.1.1
            to 7.1.3 (inclusive) the aggregate amount of all Distributions
            (being an amount equal to the aggregate amount of all cash
            Distributions and the value (as determined in accordance with clause
            3.3) of all non-cash Distributions) made by the Company in
            connection with such Partial Liquidity Event; and

      (b)   with respect to a Partial Liquidity Event described in clauses 7.1.4
            to 7.1.6 (inclusive) the aggregate of all of the Individual
            Transaction Values in relation to such Partial Liquidity Event;

            where:

            "INDIVIDUAL TRANSACTION VALUE" in relation to each Investor
            transferring shares or in the case of an amalgamation or merger,
            surrendering shares for consideration as envisaged by clause 7.1.5,
            as part of any Partial Liquidity Event, the Implied Value in
            relation to that transfer or surrender of shares by that Investor as
            part of that Partial Liquidity Event multiplied by the Applicable
            Fraction in relation to that transfer or surrender of shares by that
            Investor as part of that Partial Liquidity Event;

                                       24
<PAGE>

            "IMPLIED VALUE" shall mean in relation to the transfer or surrender
            of any shares of common stock by any Investor as part of any Partial
            Liquidity Event, the per common share consideration received by that
            Investor, net of all transaction and brokerage costs, and (subject
            to clause 3.4) net of the maximum amount of consideration due to
            that Investor that may be held back in any escrow arrangements,
            multiplied by the number of shares of common stock of the Company in
            issue at the date of such transfer or surrender, immediately prior
            to such transfer or surrender, on a Fully Diluted Basis; and

            "APPLICABLE FRACTION" shall mean a fraction, the numerator of which
            is the number of shares of common stock in the Company transferred
            or surrendered by that Investor on such Partial Liquidity Event, and
            the denominator of which is the total number of shares of common
            stock in the Company [in issue] on the date of such transfer or
            surrender, immediately prior to such transfer of surrender on a
            Fully Diluted Basis.

3.3   In the event that any part of the Distribution made in connection with a
      Partial Liquidity Event arising under clause 7.1.1, to 7.1.3 (inclusive)
      or the consideration received by any Investor in connection with a Partial
      Liquidity Event arising under clauses 7.1.4 to 7.1.6 (inclusive) consists
      of assets other than cash (excluding the right to be paid a sum in cash or
      receive a non-cash asset on a future date (whether or not, in the case of
      cash that sum is quantifiable on the Relevant Date) which rights shall be
      taken into consideration in accordance with the provisions of clause 3.4)
      the value of such assets shall be determined in good faith by the Board
      within 30 days of the Relevant Date.

3.4   In the event that:

      3.4.1 in relation to a Partial Liquidity Event arising under clauses 7.1.1
            to 7.1.3 (inclusive), either:

            3.4.1.1  a Distribution is declared, but not immediately paid; or

            3.4.1.2  more than one Distribution is declared in relation to such
                     Partial Liquidity Event; or

      3.4.2 in relation to a Partial Liquidity Event arising under clauses
            7.1.4, 7.1.5 or 7.1.6 either:

            3.4.2.1  the consideration payable in relation to that Partial
                     Liquidity Event includes a right to be paid a sum in cash
                     or to receive a non-cash asset on a future date; or

                                       25
<PAGE>

            3.4.2.2  any amount of cash which is deducted from, or any assets
                     which are withheld from, the amount payable or the assets
                     transferred to, the relevant Investors and placed into
                     escrow, is released from escrow to the relevant Investors;

      and, as a result of which either the shareholders of the Company or the
      relevant Investors (as applicable) receive additional cash or other assets
      on a future date ("DEFERRED PAYMENT") then each date or dates on which any
      such Deferred Payment becomes payable to the shareholders of the Company
      or the relevant Investors (as applicable) shall constitute an additional
      Relevant Date in relation to that Partial Liquidity Event and shall
      trigger an additional obligation on the Board to determine the Transaction
      Value in accordance with clause 3.5 as if such event constituted a
      separate Partial Liquidity Event (and an additional obligation of the
      Company to make an additional Partial Liquidity Contribution in relation
      to that Partial Liquidity Event) and, for the avoidance of doubt the
      payment of any cash or the transfer of any assets, released from any
      escrow or similar arrangements to any relevant Investors (whether before
      or after any subsequent Full Liquidity Event) shall trigger such
      obligations on the part of the Board and the Company. If, in accordance
      with the foregoing provisions of this clause 3.4, a release of additional
      consideration to Investors from an escrow (or similar) arrangement is made
      after a Full Liquidity Event, in calculating the additional Partial
      Liquidity Contribution due, the Equity Value of the Full Liquidity Event
      shall be taken into account when determining whether the Transaction Value
      Threshold has been met or exceeded, and for determining "X" for the
      purposes of clause 2.7.1. Notwithstanding the foregoing, if any payment
      that would be required to be made pursuant to this clause 3.4 after the
      Relevant Date of a Full Liquidity Event would have resulted in a reduction
      of the amount payable pursuant to clauses 2.4 and 2.5 if such payment
      pursuant to this clause 3.4 had been made prior to the Determination Date
      of such Full Liquidity Event, then such payment otherwise required by this
      clause 3.4 shall be reduced to the extent of such otherwise resulting
      reduction (but not below zero).

3.5   Subject to clause 3.6 within 30 days of the Relevant Date of a Full
      Liquidity Event or a Partial Liquidity Event (including, for the avoidance
      of doubt, each Relevant Date relating to the same Partial Liquidity Event
      pursuant to clause 3.4) the Board shall determine the Equity Value in
      accordance with clause 3.1 (with respect to Full Liquidity Events) or the
      Transaction Value in accordance with clauses 3.2 to 3.4 inclusive (with
      respect to Partial Liquidity Events), and shall give written notice of
      their determination to the Company and the Trustee within such 30-day
      period the date of such notice being, in each case, the "DETERMINATION
      Date" in relation to such Full Liquidity Event or Partial Liquidity Event,
      save in relation to (a) a Partial Liquidity Event in respect of which no
      Partial Liquidity Contribution is due by virtue of the fact that the
      Transaction Value Threshold has not been reached, in which case, the
      Determination Date in relation to that Partial Liquidity

                                       26
<PAGE>

      Event shall be the Determination Date (if any) of the first Partial
      Liquidity Event in respect of which a Partial Liquidity Contribution is
      made pursuant to clause 2.7; and (b) if the Full Liquidity Event is a
      Liquidation then the Determination Date shall be the date on which the
      Liquidator makes a distribution to shareholders of a substantial
      proportion of the assets available for distribution in the Liquidation.

3.6   In the event that a Full Liquidity Event also triggers an obligation to
      calculate Total Equity Value (as defined in the Viatel Convertible Loan
      Notes) then Equity Value shall be determined in accordance with the same
      procedure as is set out in Section 4.3(b) of the Viatel Convertible Notes
      for the determination of Total Equity Value (which, for the avoidance of
      doubt means that negotiations between the Board and the holders of the
      Viatel Convertible Notes shall, so far as they are relevant for the
      calculation of Equity Value, bind the Trustee) but adjusted as
      contemplated by clause 3.1 hereof, and the Board shall give written notice
      to the Company and the Trustee of the Equity Value, within 10 Business
      Days of the date on which the "EQUITY VALUE" is agreed or determined
      pursuant to such procedure and the date of such notice shall, unless such
      Full Liquidity Event is a Liquidation, constitute the "DETERMINATION DATE"
      in relation to that Full Liquidity Event. If the Full Liquidity Event is a
      Liquidation then the Determination Date shall be the date on which the
      Liquidator makes a distribution to shareholders of a substantial
      proportion of the assets available for distribution in the Liquidation.

4.    CESSATION OF EMPLOYMENT OF THE RELEVANT EMPLOYEE

4.1   If the Relevant Employee ceases to be an employee of a member of the Group
      (and does not immediately become an employee of another member of the
      Group) due to:

      4.1.1 the Company or another member of the Group terminating the Relevant
            Employee's employment without Cause; or

      4.1.2 the Relevant Employee terminating his employment for Good Reason; or

      4.1.3 the Relevant Employee's death or disability (disability for these
            purposes being as determined by the Remuneration Committee),

      the amount of the Maximum Percentage Contribution which shall be deemed to
      have vested (as contemplated by clause 2.4.2) in relation to a Full
      Liquidity Event, the Trigger Date of which occurs following the Date of
      Cessation but on or prior to 21 April 2014, shall be increased by assuming
      that the Relevant Employee's Date of Cessation falls into the "Tranche"
      immediately following the "Tranche" in which the Date of Cessation falls
      for the purposes of clause 2.4.2. Any part of the Maximum Percentage
      Contribution which does not vest in accordance with this clause 4.1 (or is
      not accellerated in accordance with clause 2.4.2(b)) shall lapse
      automatically at the Date of Cessation.

                                       27
<PAGE>

4.2   For the purpose of clause 4.1 above:

      4.2.1 "CAUSE" means (i) the grounds on which the Relevant Employee's
            employment may be summarily terminated without further payment to
            the Relevant Employee as set out in clause 11.4 of the Service
            Agreement; and/or (ii) the Relevant Employee's failure to
            satisfactorily perform (as determined by the CEO) the duties set out
            in his Service Agreement or assigned to him by the CEO or his
            immediate line manager and/or (iii) the Relevant Employee's failure
            to achieve the objectives assigned to him by the CEO or his
            immediate line manager.

      4.2.2 The Relevant Employee's employment will be terminated by him with
            "Good Reason" if he resigns in circumstances where the Company (or
            the Group Company which is his employer, if different) is in
            fundamental breach of its obligations under his Service Agreement
            such that on the balance of probabilities the circumstances of the
            resignation amount to constructive dismissal as determined within 15
            Business Days of appointment by a barrister of at least 7 years'
            standing appointed jointly by the Company and the Relevant Employee.
            The cost of such appointment shall be paid by the Company if the
            barrister determines that on the balance of probabilities the
            circumstances did amount to constructive dismissal and otherwise by
            the Relevant Employee.

4.3   Subject to the provisions of clause 2.4.2(b), if the Relevant Employee
      ceases to be an employee of a member of the Group (and does not
      immediately become an employee of another member of the Group ) for any
      reason other than those set out in clause 4.1 above, the Trustee will be
      entitled, upon the Payment Due Date in relation to any Full Liquidity
      Event the Trigger Date of which occurs following the Date of Cessation but
      on or prior to 21 April 2014, to be paid (with respect to the Relevant
      Employee) only that part of the Maximum Percentage Contribution which has
      vested on or prior to the Date of Cessation and will be paid that amount
      by the Company in accordance with clause 2.1. In such event, any part of
      the Maximum Contribution in relation to a Full Liquidity Event which has
      not vested prior to such Date of Cessation shall lapse automatically at
      the Date of Cessation.

5.    PAYMENT OF PARTIAL LIQUIDITY CONTRIBUTIONS, CONTRIBUTIONS AND ADDITIONAL
      CONTRIBUTIONS WHERE CONSIDERATION IS PAYABLE OTHERWISE THAN IN CASH

5.1   In the event that:

      5.1.1 a Partial Liquidity Event requiring a Partial Liquidity Contribution
            occurs; or

                                       28
<PAGE>

      5.1.2 a Full Liquidity Event occurs;

      and in any case, the amounts payable to the shareholders of the Company
      and/or relevant Investors (as applicable) in relation to such Partial
      Liquidity Event and/or Full Liquidity Event are not payable wholly in cash
      or Liquid Consideration ("NON-LIQUID PAYMENT") then the following
      provisions of this clause 5 shall apply.

5.2   To the extent that, in relation to any Full Liquidity Event or Partial
      Liquidity Event the amount payable to the shareholders of the Company
      and/or relevant Investors (as applicable) is payable in cash, then the
      same pro rata portion of the Partial Liquidity Contribution, in relation
      to a Partial Liquidity Event, or the Contribution (and, if applicable,
      Additional Contribution) in relation to a Full Liquidity Event shall be
      payable in cash.

5.3   To the extent that, in relation to any Full Liquidity Event or Partial
      Liquidity Event, the amount is to be satisfied by Liquid Consideration
      then:

      5.3.1 the Company shall use reasonable endeavours prior to the relevant
            Payment Due Date, to ensure that the Partial Liquidity Contribution,
            in relation to a Partial Liquidity Event, or the Contribution (and,
            if applicable, Additional Contribution) in relation to a Full
            Liquidity Event, can be satisfied entirely in cash; but

      5.3.2 if the Company having used reasonable endeavours to ensure payment
            in cash pursuant to clause 5.3.1 prior to the relevant Payment Due
            Date, is unable to do so on a basis reasonably satisfactory to the
            Board, then the Company shall be entitled to satisfy its obligation
            to make the Partial Liquidity Contribution, in relation to a Partial
            Liquidity Event or the Contribution (and, if applicable, Additional
            Contribution) in relation to a Full Liquidity Event, and the Trustee
            shall be bound to accept satisfaction of the Partial Liquidity
            Contribution, or the Contribution and, if applicable, Additional
            Contribution (as appropriate) by transfer into the EBT of such
            amount of the Liquid Consideration as has a value (in the discretion
            of the Remuneration Committee) equal to the amount of the Partial
            Liquidity Contribution or Contribution and, if applicable,
            Additional Contribution (as appropriate) which is not payable in
            cash pursuant to clause 5.2.

5.4   To the extent that in relation to any Full Liquidity Event or Partial
      Liquidity Event, the amount is to be satisfied by a Non-liquid Payment,
      then the Company shall satisfy its obligation to make the Partial
      Liquidity Contribution, in relation to a Partial Liquidity Event or the
      Contribution (and, if applicable, Additional Contribution) in relation to
      a Full Liquidity Event, and the Trustee shall be bound to accept
      satisfaction of the Partial Liquidity Contribution or the Contribution
      and, if applicable, Additional Contribution (as appropriate) by transfer
      into the EBT of (at the discretion of the Board) either: (a) such

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<PAGE>

      amount of the Non-liquid Payment as has a value (in the discretion of the
      Board) equal to the amount of the Partial Liquidity Contribution or
      Contribution and, if applicable, Additional Contribution (as appropriate)
      which is not payable in cash or Liquid Consideration pursuant to clauses
      5.2 and/or 5.3 and for the avoidance of doubt, if the Non-liquid Payment
      constitutes shares which are subject to restrictions on sale, the
      Trustee's entitlement hereunder shall be to receive such shares subject to
      equivalent restrictions on sale as those applicable to the shares received
      by the Company and/or the relevant Investors (as applicable); or (b) an
      amount of cash equal to the amount of such Partial Liquidity Contribution
      or Contribution and, if applicable, Additional Contribution (as
      appropriate).

5.5   Notwithstanding anything to the contrary in this covenant, neither:

      5.5.1 complying with the obligation to use "reasonable endeavours" in
            clause 5.3.1; nor

      5.5.2 any other provision of this covenant will oblige the shareholders of
            the Company, any of the Investors or any other person to incur
            costs, fees or expenses in connection with the conversion of any
            amount of Liquid Consideration into cash, which in the aggregate are
            in excess of 1% of the total value of that amount of Liquid
            Consideration.

6.    FULL LIQUIDITY EVENT

6.1   A Full Liquidity Event shall be the first occurrence of any of the
      following events:

      6.1.1 a Sale; or

      6.1.2 a Liquidation of the Company,

      and under no circumstances shall there be more than one Full Liquidity
      Event pursuant to this covenant.

7.    PARTIAL LIQUIDITY EVENT

7.1   A Partial Liquidity Event shall be the occurrence of any of the following
      events, in each case prior to a Full Liquidity Event:

      7.1.1 the transfer of any Material Asset including without limitation an
            amalgamation or merger of a Material Subsidiary, to or with a person
            or entity that is not a Qualified Transferee whether in one
            transaction or a series of related transactions (but excluding a
            transfer or amalgamation or merger by one member of the Group to
            another member of the Group) but only if followed by a Distribution
            of proceeds of

                                       30
<PAGE>

            such transfer to the Investors and/or (if appropriate as determined
            by the Board) their Qualified Transferees;

      7.1.2 the Liquidation of a Material Subsidiary followed by a Distribution
            of proceeds of such Liquidation to the Investors and/or (if
            appropriate as determined by the Board) their Qualified Transferees;

      7.1.3 a Post-Flotation Transfer of shares in a Controlling Subsidiary but
            only if followed by a Distribution of proceeds of such transfer to
            the Investors and/or (if appropriate as determined by the Board)
            their Qualified Transferees;

      7.1.4 a Tag-Along Transaction (which is not a Sale);

      7.1.5 an amalgamation or merger of the Company which is not a Sale but
            results in the receipt by Investors of proceeds as consideration in
            exchange for the surrender of common stock of the Company (it being
            understood that interests in the Company or in a successor thereto
            are not such proceeds, and an amalgamation or merger by which the
            Company is making an acquisition is not a Partial Liquidity Event);
            or

      7.1.6 a Post-Flotation Transfer of shares in the Company (which is not a
            Sale);

      and for the purposes of this covenant, and in accordance with clause 8, if
      an event or series of events could be classified as a Partial Liquidity
      Event under more than one sub-clause of this clause 7.1, the Board shall
      determine which, if any, subsection applies, but no event or series of
      events shall be deemed to constitute two or more separate Partial
      Liquidity Events simply because such event or series of events could be
      considered a Partial Liquidity Event under more than one such sub-clause.
      The Board shall have the responsibility to determine if an amalgamation or
      merger of the Company is one in which the Company is making an
      acquisition.

8.    MULTIPLE LIQUIDITY EVENTS

      In the event that more than one Event (as defined below) occurs as part of
      one single transaction or a series of closely connected transactions, then
      the Board shall determine which provisions of this covenant shall apply
      and, if necessary, any adjustment to the provisions of this covenant which
      should be made to ensure that the provisions of this covenant operate
      fairly as between the Company and the Trustee and for the avoidance of
      doubt but without limitation, shall be entitled (in its sole discretion)
      to find that a Partial Liquidity Event and a Reorganisation can both take
      place pursuant to this covenant and shall be entitled (in its sole
      discretion) to find that any particular Partial Liquidity Event is not
      also a Reorganisation. For the purposes of this clause 8, each or any of a
      Partial Liquidity Event, a Full Liquidity Event and a Reorganisation shall
      constitute an "EVENT".

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<PAGE>

9.    REORGANISATION

      In the event that at any time prior to a Full Liquidity Event a
      Reorganisation occurs, the Company shall (so far as it is legally able)
      ensure that the body corporate principally surviving or resulting from the
      Reorganisation, or the new holding company of the Group following the
      Reorganisation, ("NEWCO"), or, in the case of a Reorganisation under
      sub-paragraph (d) of the definition of Reorganisation, the Company,
      covenants to the Trustee on identical or substantially similar terms to
      the terms of this covenant (in any event, reasonably acceptable to the
      Board, taking into account the intentions of the parties to this covenant)
      so that the Relevant Employee should be in the same economic position
      (taking account of any ongoing obligations of any other entity that holds
      or retains assets of the Group and taking into account the principles of
      Section 3.1 hereof and Schedule 3 of the Investment Agreement) following
      the Reorganisation as he was before. Such covenant may be contingent upon
      the Company receiving a release (in form and substance reasonably
      acceptable to it) from all obligations (other than accrued obligations,
      unless these are also assumed by Newco) hereunder.

10.   ADMINISTRATION

10.1  Any notice or other document which the Company is required or may desire
      to give to the Trustee pursuant to this covenant shall be sufficiently
      given if delivered to it by post in a prepaid cover addressed to the
      Trustee at its registered office and if so sent shall be deemed to have
      been duly given on the date of posting.

10.2  Any notice or other document which the Trustee is required or may desire
      to give to the Company pursuant to this covenant shall be sufficiently
      given if delivered to it by post in a prepaid cover addressed to the
      Company at its registered office and if so sent shall be deemed to have
      been duly given on the date of posting.

11.   CONTRACTS (RIGHTS OF THIRD PARTIES) ACT 1999

      A person who is not the Trustee or a company who is not a member of the
      Group has no right under the Contracts (Rights of Third Parties) Act 1999
      to rely upon or enforce any provisions of this covenant.

12.   GOVERNING LAW AND COUNTERPARTS

12.1  This covenant is governed by and shall be interpreted in accordance with
      the laws of England.

12.2  This covenant may be executed in one or more counterparts, each of which
      when executed and delivered shall be an original but when taken together
      shall constitute one and the same instrument.

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<PAGE>

13.   DISPUTE RESOLUTION

13.1  The parties shall use their best efforts to negotiate in good faith and
      settle amicably any dispute that may arise out of or relate to this
      covenant (or its construction, validity or termination) (a "DISPUTE"). If
      a Dispute cannot be settled through negotiations by appropriate
      representatives of the Trustee and the Board then either party may give to
      the other a notice in writing (a "DISPUTE NOTICE"). Within seven days of
      the Dispute Notice being given the parties shall refer the Dispute to the
      chairman of the Board, in the case of the Company, and the managing
      director, in the case of the Trustee, who shall meet in order to attempt
      to resolve the dispute. If the Dispute is not settled by agreement in
      writing between the parties within 14 days of the Dispute Notice it shall
      be resolved in accordance with clauses 13.2 and 13.3.

13.2  If a Dispute is not successfully resolved in accordance with clause 13.1,
      such Dispute shall be referred to mediation in accordance with the Centre
      for Dispute Resolution ("CEDR") Model Mediation Procedure. The mediation
      shall be conducted by a single mediator appointed by mutual agreement, or
      (failing mutual agreement within seven days of a notice from either party
      to the other calling upon the other so to agree) by the CEDR/President of
      the London Chamber of Commerce. Both parties agree to co-operate fully
      with such mediator, provide such assistance as is necessary to enable the
      mediator to discharge his duties, and to bear equally between them the
      fees and expenses of the mediator.

13.3  If the Dispute is not settled by agreement in writing between the parties
      within 30 days after the appointment of a mediator, or such other period
      as the parties may agree, it shall be referred to a single arbitrator to
      be agreed between the parties. Failing such agreement within 30 days of
      the request by one party to the other that a matter be referred to
      arbitration in accordance with this clause such reference shall be to an
      arbitrator appointed by the President for the time being of the
      International Chamber of Commerce ("ICC") in London. The arbitration shall
      be conducted in London in the English language in accordance with the
      arbitration rules of the ICC in force at the date of this covenant. The
      decision of such arbitrator shall be final and binding upon the parties.
      Any reference under this clause shall be deemed to be a reference to
      arbitration within the meaning of the Arbitration Act 1996.

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<PAGE>

13.4  The parties shall keep confidential and not use for any collateral or
      ulterior purpose the subject matter of the arbitration and all
      information, documents and materials produced for, or arising in relation
      to, the arbitration including any award arising out of it except insofar
      as is necessary to implement and enforce any award or otherwise as
      required by law.

THIS COVENANT is entered into as a DEED and is executed and delivered by or on
behalf of the parties on the date set out at the top of page one.

THE COMMON SEAL of                    )
VIATEL HOLDING (BERMUDA) LIMITED      )
was affixed to this Deed              )
in the presence of                    )

__________________________________
Authorised Person

__________________________________
Authorised Person

THE COMMON SEAL of                    )
EB TRUSTEES LIMITED                   )
was affixed to this Deed              )
in the presence of                    )

__________________________________
Authorised Person

__________________________________
Authorised Person

                                       34
<PAGE>

                                     ANNEX A

                            AGREED FORM WAIVER LETTER

I, [               ] of [                       ], hereby waive all and any
rights I may have to participate in an equity compensation plan as set out in
[                                 ] of my [service/employment] agreement
dated [             ] with [Viatel Holding (Bermuda) Limited/VTL (UK) Limited].

Executed and delivered as a deed on ________________ 2005

by: __________________________________

[               ]

Witnessed by:

______________________________________
Signature

______________________________________
Name

______________________________________
______________________________________
______________________________________
Address

______________________________________
Occupation

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