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                                                                    EXHIBIT 10.4
                                 LONDON SWITCH

                             DATED 11 NOVEMBER 1999

                        WORLDPORT COMMUNICATIONS INC.(1)

                      WORLDPORT COMMUNICATIONS LIMITED(2)

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                                   AGREEMENT
                          FOR THE SALE AND PURCHASE OF
                           NORTEL 250 DMS GSP SWITCH

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DATE 11 November 1999

PARTIES

     (1) WORLDPORT COMMUNICATIONS INC. incorporated in the State of Delaware
whose principal executive offices are at 1825 Barrett Lakes Boulevarde, Suite
1000 Kennesaw, Georgia 30144, United States of America ("VENDOR"); and

     (2) WORLDPORT COMMUNICATIONS LIMITED with company number 03200002 whose
registered office is at 1st Floor, Bouverie House, 154 Fleet Street, London EC4A
2DQ ("PURCHASER")

INTRODUCTION

     (A) The Vendor has agreed to dispose of its interest in the Nortel 250 DMS
GSP switch together with the benefit of certain contracts to the Purchaser on
the terms of this agreement.

     (B) Simultaneously with the disposal of the Nortel 250 DMS GSP switch
together with the benefit of certain contracts, the Vendor has agreed to sell to
Energis plc, which will following the Completion Date, will be the Purchaser's
ultimate holding company, the Vendor's holding of shares in the Purchaser and
the Vendor's holding of shares in WorldPort Communications Europe Holding BV.

OPERATIVE PROVISIONS

     1 INTERPRETATION

     1.1 In this Agreement (including the Introduction and the Schedules),
except where a different interpretation is necessary in the context, the
following words and expressions shall have the following meanings:

"ASSETS"                     the Contracts and the Switches;

"COMPLETION"                 completion of this Agreement pursuant to the terms
                             of clause 4;

"COMPLETION DATE"            the date five business days after the satisfaction
                             of the conditions set out in clause 2 or such other
                             date as may be agreed between the parties;

"CONSIDERATION"              the consideration payable in accordance with clause
                             4;

"CONTRACTS"                  the agreements referred to in Schedule 1 to this
                             Agreement;

"ENCUMBRANCES"               any option, right to acquire, mortgage, charge,
                             pledge, liens or agreement for payment on deferred
                             terms, retention of title, judgment or other
                             security, encumbrance or equity whatsoever

"ENERGIS PLC"                Energis plc whose registered office is at
                             Carmelite, 50 Victoria Embankment, London, EC4Y
                             OPE:

"INTELLECTUAL PROPERTY
RIGHTS"                      patents, trade marks, service marks, trade names,
                             domain names, registered designs, designs,
                             semiconductor topography rights, database rights,
                             copyrights and other forms of intellectual or
                             industrial property (in each case in any part of
                             the world, whether or not registered or
                             registrable), know-how, inventions, formulae,
                             confidential or secret processes and information,
                             rights in computer software, and any other
                             protected rights and assets, and any licenses and
                             permissions in connection with the foregoing

"UK SWITCH"                  the Nortel 250 DMS GSP Switch with 448 ports and
                             approximate capacity of 100 million minutes per
                             month located at London, Telehouse, further details
                             of which are set out in Schedule 2 to this
                             Agreement

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"VENDOR'S SOLICITORS"        Rakisons, Clements House, 14/18 Gresham Street,
                             London EC2V 7JE

"WCEH"                       WorldPort Communications Europe Holding B.V. having
                             its statutory seat in Rotterdam The Hague

"WCL"                        WorldPort Communications Limited

"WCEH SHARE AGREEMENT"       the agreement in the agreed form of even date made
                             between WorldPort, the Vendor and Energis plc
                             whereby WorldPort agrees to sell 85% of the issued
                             share capital of WCEH

"WCL SHARE AGREEMENT"        the agreement in the agreed form of even date made
                             between the Vendor and Energis plc hereby the
                             Vendor agrees to sell the entire issued share
                             capital of WCL

"WORLDPORT"                  WorldPort International Inc, incorporated in the
                             State of Delaware whose principal executive offices
                             are 1825 Barrett Lakes Boulevard, Suite 1000
                             Kennesaw, Georgia 30144, United State of America

"YEAR 2000 COMPLIANT"        neither the performance nor the functionality of
                             assets when in normal use will be materially
                             impaired by the advent of the Year 2000 and in
                             particular:

                             (a) Year 2000 Compliant shall mean that no value
                                 for current date will cause any interruption or
                                 error in the option of the assets;

                             (b) all manipulations of time-related data by the
                                 assets will produce the desired results for all
                                 valid date values prior to, through and beyond
                                 the Year 2000;

                             (c) date elements in these products (including
                                 interfaces and data storage) will permit
                                 specifying the century to eliminate date
                                 ambiguity without human intervention including
                                 leap year calculations; and

                             (d) where any data element is represented without a
                                 century, the correct century shall be
                                 unambiguous for all manipulations involving
                                 that element

     1.2 References to the parties or clauses or Schedules are references to the
parties and clauses of or Schedules to this Agreement.

     1.3 Headings to clauses are for information only and shall not form part of
the operative provisions of this Agreement.

     2 CONDITIONS PRECEDENT

     2.1 This agreement shall be subject to the fulfilment at or prior to the
Completion Date of each of the following conditions (unless waived by each of
the parties):

          (a) this agreement and the other transactions contemplated shall have
     been approved and adopted by the requisite vote of the shareholders of the
     Vendor; and

          (b) the completion of the WCEH Share Agreement with the Purchaser.

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     2.2 The obligations of the Purchaser to complete the transactions
contemplated is subject to the fulfilment of all of the following conditions on
or prior to the Completion Date:

          (a) each and every warranty made by the Vendor shall have been true
     and correct in all material respects when made and shall be true and
     correct in all material respects as if originally made on and as at the
     Completion Date except to the extent that such warranties are not true and
     correct in all material respects as a result of;

             (i) an event or occurrence outside the control of the Vendor
        occurring during the period from the execution of this Agreement until
        the Completion Date;

             (ii) any act or omission of the Purchaser during the period from
        the execution of this Agreement until the Completion Date;

             (iii) any action taken by the Vendor in the ordinary cause of
        business during the period from the execution of this Agreement until
        the Completion Date.

          (b) the Vendor shall have executed or procured on terms reasonably
     satisfactory to the Purchaser an agreement in writing granting to the
     Purchaser access to the UK Switch.

     3 SALE AND PURCHASE OF THE ASSETS

     3.1 The Vendor shall sell with full title guarantee and the Purchaser shall
purchase all rights, title and interest of the Vendor in and to the Assets
subject only to the terms and the obligations under the Contracts and otherwise
free and clear of Encumbrances.

     3.2 Risk in UK Switch shall pass to the Purchaser with effect from the
close of business on the Completion Date.

     4 CONSIDERATION PAYABLE BY THE PURCHASER

     4.1 The total purchase consideration payable by the Purchaser to acquire
the Assets shall be the amount provided for in the WCL Share Agreement.

     4.2 All sums payable by the Purchaser in respect of the Consideration shall
be paid in cash at Completion.

     5 COMPLETION

     5.1 Completion of the sale and purchase of the Assets shall take place on
the Completion Date at the offices of the Vendor's Solicitors or at such other
place as may be mutually agreed.

     5.2 Upon and after Completion the Vendor shall (subject to the terms of
this Agreement) do and execute all other necessary acts, deeds, documents and
things within its power effectively to vest the Assets in the Purchaser and,
pending the doing and executing of such acts, deeds, documents and things the
Vendor shall hold the legal estate in such Assets in trust for the Purchaser.

     6 THE CONTRACTS

     6.1 With effect from the Completion Date the Purchaser shall be entitled to
all the benefits of the Vendor under, and will perform all the obligations and
liabilities arising under the Contracts.

     6.2 The Vendor and the Purchaser shall prior to Completion each negotiate
in good faith with the counterparty to each of the Contracts for the novation of
the Contracts for nil consideration and on terms whereby the Purchaser
undertakes to perform each Contract and to be bound by all the terms thereof as
if the Purchaser was as from the Completion Date party thereto in lieu of the
Vendor and whereby each Contractor releases and discharges the Vendor from all
claims and demands whatsoever in respect thereof arising after the Completion
Date and whereby the Contractors accept the liability of the Purchaser in lieu
of the liability of the Vendor in every way as if the Purchaser was named
therein as party thereto in place of the Vendor as from the Completion Date.

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     6.3 If a counterparty does not agree to enter into a novation agreement in
respect of a Contract, the Vendor and the Purchaser shall, prior to Completion,
each enter into such documentation as shall be required to assign the benefit
(subject to the burden) of those of the Contracts for which a deed of novation
is not entered into, by virtue of which the Purchaser undertakes to perform such
Contracts and to be bound by all the terms thereof with effect from the
Completion Date.

     6.4 In any case where the consent of a counterparty is required to the
assignment from the Vendor to the Purchaser of any Contract, and such consent
has not been duly obtained, the assignment of that Contract shall be conditional
upon such consent and pending the grant of such consent, the Vendor shall hold
its rights under the relevant Contract on trust for the Purchaser.

     6.5 Whether or not any novation agreement is entered into, the Vendor shall
indemnify the Purchaser on a full indemnity basis from and against all costs,
claims, proceedings and demands (whether in contract or in tort or otherwise
arising in respect of any period before the Completion Date in connection with
the Assets.

     6.6 Subject to clause 6.4, whether or not any novation agreement is entered
into, the Purchaser shall indemnify the Vendor on a full indemnify basis from
and against all costs, claims, proceedings and demands (whether in contract or
in tort or otherwise) arising in respect of any period after the Completion Date
in connection with the Assets.

     7 WARRANTIES

     7.1 The Vendor warrants to the Purchaser as follows:

          (a)(i) that the Purchaser shall acquire the Assets free from all
     Encumbrances, subject only to the Contracts;

             (ii) that the UK Switch as of the Completion Date complies with all
        material statutory requirements and regulations relating to its
        operation;

             (iii) so far as the Vendor is aware use of the UK Switch by or on
        behalf of the Purchaser will not infringe the Intellectual Property
        Rights of any third party;

             (iv) so far as the Vendor is aware the UK Switch is Year 2000
        Compliant; and

             (v) the Contracts are true, complete and accurate in all material
        respects and are in full force and effect and that no written notice of
        termination for breach has been received by the Vendor;

          (b) that discussions have taken place with Forsythe McArthur
     Associates, Inc ("FMA") and Comdisco, pursuant to which FMA and Comdisco
     have indicated to the Vendor that they will consider the sale and/or lease
     of the UK Switch to interested parties and the novation of the relevant
     Contracts under mutually agreeable terms and conditions.

     8 ANNOUNCEMENTS

     8.1 No announcement of any kind shall be made in respect of the subject
matter of this Agreement except as specifically agreed between the Vendor and
the Purchaser or as required by law.

     8.2 Notwithstanding clause 8.1, the Vendor and the Purchaser shall procure
as soon as practicable after Completion that appropriate notices are given to
each Contractor of the assignment or proposed novation of each relevant Contract
by the Vendor to the Purchaser.

     9 GENERAL PROVISIONS

     9.1 Either party may at its absolute discretion in whole or in part
release, compound or compromise, or grant time or indulgence to the other party
for any liability under this Agreement without affecting its rights against the
other party under the same or any other liability.

     9.2 No party shall, prior to Completion, divulge to any third party (other
than their respective professional advisers) the fact that this Agreement has
been entered into or any information regarding its

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terms or any matters contemplated by this transaction or make any announcement
relating to it without the prior written consent of the other party.

     9.3 The express or implied waiver by any party of any of its rights under
this Agreement shall constitute neither a continuing waiver of the right waived
nor a waiver of any other right under this Agreement.

     9.4 Nothing in this Agreement shall constitute or be deemed to constitute a
partnership between the parties.

     9.5 This Agreement is personal to the parties and shall not be capable of
assignment without the prior written consent of the other party (such consent
not to be unreasonably withheld).

     9.6 If any provision of this Agreement is held to be invalid or
unenforceable, then such provision shall (so far as it is invalid or
unenforceable) be given no effect and shall be deemed not to be included in this
Agreement but without invalidating any of the remaining provisions of this
Agreement.

     9.7 Any notices must be in writing and may be given to either party at its
registered office or to such other address as may have been notified to the
other parties and will be effectively served:

          (a) on the day of receipt where any hand-delivered letter, telex or
     telefax message is received on a business day before or during normal
     working hours;

          (b) on the following business day, where any hand-delivered letter,
     telex or telefax message is received either on a business day after normal
     working hours or on any other day; or

          (c) on the second business day following the day of posting from
     within the United Kingdom of any letter sent by post office inland first
     class mail postage prepaid.

     9.8 This Agreement is governed by and is to be construed in accordance with
English law.

     IN WITNESS WHEREOF this Agreement has been executed as a Deed the day and
year first above written

                                          ATTESTATIONS

                                          SIGNED for and on behalf of
                                          WORLDPORT COMMUNICATIONS INC


                                          /s/ Carl Grivner
                                          --------------------------------------
                                          Carl Grivner

                                          SIGNED for and on behalf of
                                          WORLDPORT COMMUNICATIONS LIMITED


                                          /s/ Carl Grivner
                                          --------------------------------------
                                          Carl Grivner

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