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                                                                   EXHIBIT 2.5.4

                                                                  EXECUTION COPY

                               AMENDMENT NO. 4 TO
                            ASSET PURCHASE AGREEMENT

            This Amendment No. 4 (this "Amendment") to that certain Asset
Purchase Agreement, dated as of July 15, 2003, as amended prior to the date
hereof (the "Asset Purchase Agreement"), among Intelsat, Ltd., a Bermuda company
("Parent"), Intelsat (Bermuda), Ltd., a Bermuda company ("Purchaser"), Loral
Space & Communications Corporation, a Delaware corporation and a debtor and
debtor in possession ("Loral Space"), Loral SpaceCom Corporation, a Delaware
corporation and a debtor and debtor in possession ("Loral SpaceCom"), and Loral
Satellite, Inc., a Delaware corporation and a debtor and debtor in possession
(together with Loral Space and Loral SpaceCom, the "Sellers"), is entered into
as of March 5, 2004 among Parent, Purchaser and Sellers.

                               W I T N E S S E T H

            WHEREAS, the parties have previously entered into the Asset Purchase
Agreement, including Amendments No. 1, 2 and 3 thereto; and

            WHEREAS, subject to Section 18 hereof, the parties now wish to
further amend and modify the Asset Purchase Agreement on the terms and
conditions set forth herein.

            NOW THEREFORE, in consideration of the foregoing premises and the
parties' respective covenants and agreements and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged and
accepted, the parties hereto hereby agree as follows:

            SECTION 1. Definitions. Capitalized terms used but not defined
herein shall have the respective meanings ascribed to them in the Asset Purchase
Agreement.

            SECTION 2. Amendment to Section 2.5 of the Asset Purchase Agreement.

            (a) Section 2.5(d) of the Asset Purchase Agreement is hereby amended
by deleting that section in its entirety and replacing it with the following:

                  "(d)(i) If, on or prior to the Closing Date, Sellers, in
            compliance with Section 6.17 (and subject to availability of
            capacity), shall have entered into a New Lease that constitutes a
            Lease Agreement under Section 6.17, and the Lease Agreement is a
            valid and binding Contract (which is an Assumed Contract under
            Section 6.17(d), all rights under which are legally and validly
            assigned to Purchaser at Closing), then: (A) if the New Lease is an
            Assumed Contract pursuant to Section 6.17(c), the Base Price shall
            be increased by $100 million, or (B) if the New Lease is an Assumed
            Contract pursuant to Section 6.17(d), the Base Price shall be
            increased by $50 million; provided that if the services offered
            under the proposed New Lease may be used to provide direct-to-home
            satellite services, the proposed New Lease shall provide: (1)
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            that such services will not commence until Parent completes an
            initial public offering in compliance with the Open-Market
            Reorganization for the Betterment of International
            Telecommunications Act and (2) the parties thereto shall have no
            right to terminate the New Lease (in whole or in part) prior to the
            completion of that initial public offering.

                  (ii) Sellers will cause SS/L to execute and deliver at Closing
            amendments to the Purchased Satellite Procurement Agreements
            eliminating all obligations to make orbital incentive payments. On
            the Closing Date, Purchaser shall pay $12,500,000 to SS/L and the
            covenant of Sellers in Section 6.16 hereof and the closing condition
            in Section 9.1(r) shall be deemed to have been performed.

                  (iii) In consideration of the irrevocable waiver by Parent and
            Purchaser of the condition to Closing set forth in the final
            sentence of Section 9.1(j), the Base Price shall be reduced by
            $20,000,000, which payment the Parties agree shall be subject to
            adjustment following the Closing in accordance with the provisions
            of Schedule 2.5(d)(iii) attached hereto."

            (b) Section 2.5(j) of the Asset Purchase Agreement is hereby amended
by deleting that section in its entirety and replacing it with the following:

                  "(j)(i) If there is an amount owed by Sellers to Purchaser
            under Section 2.5(i) and Sellers have failed to make payment to
            Purchaser of such amount on the date provided therein, Purchaser
            may, in lieu of having a continuing claim against Sellers for such
            unpaid amount, elect, by written notice to Sellers and SS/L, to
            reduce the purchase price under the New Procurement Agreement by an
            amount equal to such unpaid amount and SS/L shall have a claim only
            against the Sellers (and not against Parent, Purchaser or any of
            their Affiliates) with respect to such reductions.

                  (ii) If the insurance proceeds received by Parent or its
            Affiliates following the Closing with respect to the loss of Telstar
            4 are less than $141 million (before giving effect to Purchaser's
            obligation to reimburse T-4 Warranty Payments), the purchase price
            payable under the New Procurement Agreement for the 85 Degrees
            Spacecraft (as defined in Annex I hereto) shall be reduced by the
            amount of such shortfall and SS/L shall have a claim only against
            the Sellers (and not against Parent, Purchaser or any of their
            Affiliates) with respect to such reduction. The amount of any such
            purchase price reduction shall be applied as a credit against the
            milestone payments as they first become due under the New
            Procurement Agreement. If the purchase price reduction exceeds the
            unpaid amount of the purchase price payable under the New
            Procurement Agreement, Sellers shall cause SS/L to pay such excess
            amount to Intelsat LLC within ten (10) Business Days of its written
            demand. Sellers acknowledge that, as of and


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            from the Closing, no Seller shall be named as a loss payee on the
            Telstar 4 insurance policies.

                  (iii) Sellers acknowledge that there will be no upward
            adjustment to Recurring Revenues or Backlog, and no downward
            adjustment to the Revenue Threshold or the Backlog Threshold to
            reflect lost Revenues or Backlog as a result of the loss of Telstar
            4, and Sellers hereby waive any right to object to the calculation
            of such Recurring Revenues or Backlog (under Section 2.5(f) or
            otherwise, including, without limitation, in any proceeding before
            the Bankruptcy Court or in any other proceeding before any
            Governmental Authority or arbitrator) as a result of the loss of
            Telstar 4."

            SECTION 3. Amendment to Section 2.7(a)(v) of the Asset Purchase
Agreement. Section 2.7(a)(v) of the Asset Purchase Agreement is hereby amended
by deleting that section in its entirety and replacing it with the following:

                  "(v) A deposit of $50 million with respect to the New
            Procurement Agreement (the "Deposit") in immediately available funds
            by wire transfer to the accounts designated, in writing, by the
            Sellers not less than three (3) Business Days prior to the Closing;
            provided that if Sellers are unable to deliver a valid, perfected,
            first priority security interest in the Deposit Collateral, as
            provided in the Deposit and Security Agreement, the Deposit shall
            not be a condition to Closing and shall only be required to be made
            when the required security interest in the Deposit Collateral,
            together with all appropriate documentation, is so delivered."

            SECTION 4. Amendment to Section 2.9 of the Asset Purchase Agreement.
Section 2.9 of the Asset Purchase Agreement. Section 2.9 is hereby amended to
read in its entirety as follows:

                  "Section 2.9. Title to Telstar 4. Notwithstanding any other
            provision of this Agreement, Purchaser will not acquire ownership of
            or title to Telstar 4, but will, unless for any reason there shall
            have been a decrease in the Base Price pursuant to Section
            2.5(b)(iii) with respect to the insurance proceeds payable with
            respect to the Total Loss (or lesser loss) of Telstar 4, be entitled
            to receipt and ownership of such proceeds, to the extent such
            proceeds are received on or after the Closing, and will reimburse
            the Sellers from such proceeds upon demand and presentation of
            appropriate documentation for payments they make to parties under
            Contracts With Warranty with respect to the insured loss ("T-4
            Warranty Payments"). For avoidance of doubt, if such proceeds are
            received prior to Closing and so reduce the Base Price, such
            proceeds shall not constitute Purchased Assets hereunder.


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                  Sellers agree to cooperate with Parent and Purchaser in the
            prosecution of all claims for insurance arising from the loss of
            Telstar 4. This cooperation shall include, without limitation and at
            no additional cost to Parent and Purchaser, the provision of
            technical assistance and support as requested by Purchaser in
            connection with: (i) interactions with Willis Inspace, the insurance
            underwriters and Lockheed Martin; (ii) provision of reports and
            notifications required in the insurance policies being assigned to
            Purchaser at the Closing such as state of health reports, notices of
            occurrence, and proofs of loss; (iii) briefings to insurance
            underwriters, which shall include assistance in responding to
            questions from the insurance underwriters; and (iv) at Purchaser's
            request, performance by Sellers of all obligations of the named
            insured relating to salvage requirements under Section 6 of the
            Telstar 4 insurance contract.

                  Each Seller, jointly and severally, represents and warrants to
            Parent and Purchaser that to their Knowledge after due inquiry, as
            of the date hereof, it has not received any oral or written notice
            that any Person will assert or is contemplating asserting any claims
            for T-4 Warranty Payments, except as noted on Schedule 2.9 hereto."

            SECTION 5. Amendment to Article 2 of the Asset Purchase Agreement.
Article of the Asset Purchase Agreement is hereby amended by adding a new
Section 2.10 as follows:

                  "Section 2.10 Replacement ABC Promissory Notes. Purchaser
agrees to enter into an agreement with ABC to indemnify ABC against any claims
or liabilities to which ABC may be subjected by reason of or in connection with
the issuance to SpaceCom of new replacement promissory notes for the five
separate promissory notes issued to Loral SpaceCom that it has advised Purchaser
and ABC have been lost, misplaced or destroyed; provided, however, that
Purchaser's obligation to indemnify ABC shall be conditioned upon the Closing
and the execution by SpaceCom of a similar indemnity agreement with ABC. If ABC
seeks indemnity from Purchaser pursuant to the foregoing, Purchaser shall so
notify Sellers and allow them the opportunity to assume the defense thereof.
Sellers agree, jointly and severally, to reimburse Purchaser within five (5)
Business Days of Purchaser's written demand, for any and all costs and expenses
it may incur in connection with fulfilling its obligation to indemnify ABC. If
Sellers fail to so reimburse Purchaser within such five (5) Business Day period,
Sellers' payment obligation shall accrue interest at the rate of eight percent
(8%) per annum until paid in full.

            SECTION 6. Amendment to Article VI of the Asset Purchase Agreement.
Article VI of the Asset Purchase Agreement is hereby amended by adding a new
Section 6.18 as follows:

                  "Section 6.18 Sale of Business.


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                  (a) Sellers hereby agree to cause the LSNS Agreement to be
            amended prior to Closing to require LSNS to cause any Person to whom
            all or substantially all of LSNS's assets (whether now owned or
            hereafter acquired) are sold, leased or otherwise transferred to
            assume, in writing, all of LSNS's obligations under the LSNS
            Agreement, on terms reasonably acceptable to Intelsat USA Sales
            Corporation.

                  (b) The Parties agree that the New Procurement Agreement shall
            include a provision requiring SS/L to cause any Person to whom all
            or substantially all of SS/L's assets (whether now owned or
            hereafter acquired) are sold, leased or otherwise transferred to
            assume, in writing, all of SS/L's obligations under the New
            Procurement Agreement, on terms reasonably acceptable to Intelsat
            LLC."

            SECTION 7. Waiver of Sections 9.1(h) and 9.1(k)(i) of the Asset
Purchase Agreement. Parent and Purchaser hereby irrevocably waive the conditions
to Closing set forth in Sections 9.1(h) and 9.1(k)(i) of the Asset Purchase
Agreement.

            SECTION 8. Waiver of Section 9.1(j) of the Asset Purchase Agreement.
Parent and Purchaser hereby irrevocably waive the condition to Closing set forth
in the final sentence of Section 9.1(j), in consideration for which the Base
Price shall be reduced as provided in Section 2 of this Amendment.

            SECTION 9. Amendment to Section 9.1(o) of the Asset Purchase
Agreement. Section 9.1(o) of the Asset Purchase Agreement is hereby amended by
deleting that section in its entirety and replacing it with the following:

                  "(o) Backlog as set forth in the Final Report (which the
            Parties agree shall be the Monthly Report as of January 31, 2004 if
            the Closing occurs on or before March 31, 2004 or such later date as
            may be extended by Purchaser in accordance with the last sentence of
            this Section 9.1(o)) shall not be less than the amount set forth in
            Schedule 9.1(o). Parent and Purchaser acknowledge that the Final
            Report shall include the Backlog under (i) that certain Amended and
            Restated Agreement, dated as of February 25, 2004 (the "Starband
            Agreement"), between Loral SpaceCom and Starband Communications
            Inc., and (ii) that certain Agreement, entered into on February 24,
            2004 and effective as of January 1, 2004 (the "LSNS Agreement"),
            between Loral SpaceCom and Loral Skynet Network Services, Inc.
            ("LSNS") fully as though such contracts were in full force and
            effect on January 31, 2004. Parent and Purchaser agree that the
            Starband Agreement and the LSNS Agreement shall be Assumed
            Contracts. Sellers agree to use Best Reasonable Efforts to cause
            Grant Thornton to deliver the Monthly Report as of January 31, 2004
            to Parent and Purchaser as soon as practicable. The Parties agree
            that Purchaser may extend the Closing Date until the date which is
            five (5) Business Days following its receipt of the Final Report."

            SECTION 10. Amendment to Annex H to the Asset Purchase Agreement.
Section 4 of Annex H is hereby amended by adding the following at the end
thereof:


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            "Section 1.1.d of the Statement of Work to the Telstar 8 Procurement
            Agreement shall be amended by deleting that section in its entirety
            and replacing it with the following:

                        Intelsat will arrange for access to its Clarksburg TT&C
                        facilities, equipment and support personnel for Bus,
                        C-band, Ku-band and Ka-band IOT. In addition, Intelsat
                        shall arrange for data lines for transmitting baseband
                        spacecraft telemetry data between Intelsat's Clarksburg
                        facility and SS/L's Palo Alto MCC. Intelsat will arrange
                        for one CONUS TT&C RF site at Clarksburg for use by the
                        Palo Alto MCC. To the extent SS/L is not already
                        contractually committed to purchase such services from
                        another vendor, SS/L agrees to obtain transfer orbit
                        services for Telstar 8 (i.e., TT&C ground station and
                        mission operations support) from Intelsat Global Service
                        Corporation under the parties' existing Master Ordering
                        Agreement."

            SECTION 11. Amendment to Annex I to the Asset Purchase Agreement.

            (a) Section 1 of Annex I to the Asset Purchase Agreement is hereby
amended by deleting the third sentence of that section and replacing it with the
following:

            "Notwithstanding the foregoing, Intelsat shall provide SS/L with an
            authorization to proceed with the Contract no later than June 30,
            2004."

            (b) Section 2 of Annex I to the Asset Purchase Agreement is hereby
amended by deleting the reference to "One Hundred Million Dollars
($100,000,000)" in the fourth sentence of that section and replacing it with
"Fifty Million Dollars ($50,000,000)."

            SECTION 12. Amendment to Annex J to the Asset Purchase Agreement.
Annex J to the Asset Purchase Agreement is hereby amended as follows:

            (a)   Annex J is amended by adding the following at the end thereof:

            "The Parties agree that the Pledge and Security Agreement to be
            entered into at Closing in connection with the New Procurement
            Agreement shall require Sellers, as a condition to Purchaser's
            obligation to fund the Deposit, to obtain an endorsement in form and
            substance satisfactory to Parent designating Intelsat LLC as loss
            payee under the insurance policies relating to the Satellite
            Collateral (as defined in Annex J to the Asset Purchase Agreement)
            and specifying that the first $50 million of insurance proceeds
            thereunder shall be paid into a cash collateral account under the
            exclusive control of Intelsat LLC."

            (b)   Attachment A to Annex J is amended by adding the following at
                  the end thereof:

                  "7. Pledge of stock of Loral Holdings Ltd."


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            SECTION 13. Certain Additional Representations and Warranties of
Sellers. Each Seller, jointly and severally, represents and warrants to Parent
and Purchaser that:

            (a) Subject to Section 17, the execution, delivery and performance
      by each Seller of this Amendment has been duly and validly authorized, and
      no additional corporate authorization or consent is required in connection
      with the execution, delivery and performance by such Seller of this
      Amendment; and

            (b) Subject to Section 17, this Amendment constitutes a valid and
      legally binding obligation of each Seller, enforceable in accordance with
      its terms.

            SECTION 14. Certain Additional Representations and Warranties of
Parent and Purchaser. Parent and Purchaser, jointly and severally, represent and
warrant to each Seller that:

            (a) Subject to Section 17, the execution, delivery and performance
      by each of Parent and Purchaser of this Amendment has been duly and
      validly authorized, and no additional corporate authorization or consent
      is required in connection with the execution, delivery and performance by
      Parent or Purchaser of this Amendment; and

            (b) Subject to Section 17, this Amendment constitutes a valid and
      legally binding obligation of each of Parent and Purchaser, enforceable in
      accordance with its terms

            SECTION 15. No Other Amendments; Continuing Effect of the Asset
Purchase Agreement. This Amendment shall not constitute an amendment or waiver
of any other provision of the Asset Purchase Agreement, the TT&C Transition
Services Agreement or the LSNS Agreement not expressly referred to herein
(including, for the avoidance of doubt and without limitation, such provisions
of Sections 2.5, 2.7, 2.9, 6.2 and 9.1 of the Asset Purchase Agreement and
Annexes H and I to the Asset Purchase Agreement, as are not expressly referred
to herein). The provisions of Section 2.5(j) as amended in accordance with
Section 2 of this Amendment shall not be exclusive of any other rights or
remedies of Parent and Purchaser under the Asset Purchase Agreement or provided
by Law. Except as expressly provided hereby, the Asset Purchase Agreement shall
continue in full force and effect in accordance with the provisions thereof and
the Asset Purchase Agreement is in all respects hereby ratified, confirmed and
preserved. This Amendment and all of its provisions shall be deemed a part of
the Asset Purchase Agreement in the manner and to the extent herein provided.

            SECTION 16. Incorporation of Article XII of the Asset Purchase
Agreement. Article XII of the Asset Purchase Agreement is incorporated herein by
reference as if set forth fully in this amendment.

            SECTION 17. Effective Date. The Parties acknowledge that this
Amendment is conditioned upon and shall become effective only upon the later of
(a) the date on which the Bankruptcy Court approves the execution, delivery and
performance of this Amendment (the "Bankruptcy Court Approval Date"), and (b)
the date on which, under the Credit Agreement, dated as of December 17, 2003, by
and among Parent, the lenders party thereto and Citicorp North America, Inc., as
Administrative Agent (the "Credit Agreement"), the Required Lenders


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(as such term is defined in the Credit Agreement) consent to the terms of this
Amendment. The Parties agree to use Best Reasonable Efforts to obtain such
approvals as promptly as practicable. If the Parties fail to obtain such
approvals by the earlier of the Bankruptcy Court Approval Date or April 12,
2004, either Sellers, on the one hand, or Parent and Purchaser, on the other
hand, may terminate this Amendment upon written notice to the other Parties.

                  [REMAINDER OF PAGE LEFT INTENTIONALLY BLANK]


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            IN WITNESS THEREOF, the parties hereto have executed or caused this
Amendment to be executed as of the date first above written.

                                   LORAL SPACE & COMMUNICATIONS CORPORATION,
                                          as debtor and debtor in possession

                                   By:      ______________________________
                                            Name:
                                            Title:

                                   LORAL SPACECOM CORPORATION,
                                          as debtor and debtor in possession

                                   By:      ______________________________
                                            Name:
                                            Title:

                                   LORAL SATELLITE, INC.,
                                          as debtor and debtor in possession

                                   By:      ______________________________
                                            Name:
                                            Title:

                                   INTELSAT, LTD.,

                                   By:      ______________________________
                                            Name:
                                            Title:

                                   INTELSAT (BERMUDA), LTD.,

                                   By:      ______________________________
                                            Name:
                                            Title:


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