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                                                                 EXHIBIT 10.16.5

                                                                  EXECUTION COPY

                                 FIFTH AMENDMENT



                   FIFTH AMENDMENT, dated as of December 15, 2000 (this
"Amendment"), to and of the Amended and Restated Credit and Participation
Agreement, dated as of November 14, 1997 (as amended, supplemented or otherwise
modified from time to time, the "Credit Agreement"), among LORAL SPACECOM
CORPORATION (the "Borrower"), SPACE SYSTEMS/LORAL, INC. ("SS/L"), the Banks from
time to time parties thereto (the "Banks"), ISTITUTO BANCARIO SAN PAOLO DI
TORINO S.P.A. ("San Paolo"), individually and as selling bank (in such capacity,
the "Selling Bank"), BANK OF AMERICA NATIONAL TRUST AND SAVINGS ASSOCIATION
("Bank of America"), as administrative agent (in such capacity, the
"Administrative Agent") and as issuing bank, THE CHASE MANHATTAN BANK, as
syndication agent and NATIONSBANK OF TEXAS, N.A., as documentation agent.

                              W I T N E S S E T H :

                   WHEREAS, the Borrower currently has outstanding receivables
(the "Globalstar Receivables") as set forth on Schedule 1 attached hereto, in
the aggregate amount at historical cost, as of December 31, 2000, of
approximately $180,000,000, owed to it by Globalstar, L.P. ("Globalstar"); and

                   WHEREAS, the Borrower has agreed to sell (the "Globalstar
Receivables Sale") the Globalstar Receivables to Loral Space & Communications
Corporation (the "Parent") for a purchase price of approximately $180,000,000
(provided that at least $130,000,000 of the purchase price is payable in cash
and the remainder if any, of such purchase price is payable in the form of a
promissory note issued by the Parent to the Borrower); and

                  WHEREAS, on or prior to the date hereof, the Borrower paid a
dividend to Parent of $70,000,000, which dividend is permitted under Subsection
9.7 of the Credit Agreement and which will be used to finance in part the cash
portion of the consideration for the Globalstar Receivables Sale; and

                  WHEREAS, in connection with the Globalstar Receivables Sale,
the Borrower has requested that the Credit Agreement be amended as more fully
set forth below; and

                  WHEREAS, the Required Banks are willing to agree to such
amendment upon terms and subject to the conditions set forth below;

                  NOW, THEREFORE, in consideration of the premises and mutual
agreements contained herein and for other valuable consideration, the receipt
and sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

                  Section 1. Defined Terms. Unless otherwise defined herein,
terms defined in the Credit Agreement are used herein (including the recitals
hereto) as therein defined.
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                  Section 2. Amendment of Subsection 1.1 (Defined Terms).
Subsection 1.1 of the Credit Agreement is hereby amended by:

                   (i) adding a proviso at the end of the first sentence of the
definition of "Consolidated EBITDA" to read in its entirety as follows:

                  "provided that, if the Globalstar Receivables Sale occurs, any
charges or write-offs associated with the Globalstar Receivables or any gains
resulting from the Globalstar Receivables Sale in each case that are recorded or
taken after October 1, 2000, shall be disregarded for the purpose of calculating
Consolidated EBITDA."

                  (ii) adding a proviso at the end of the definition of
"Consolidated Interest Expense" to read in its entirety as follows:

                  "provided that, if the Globalstar Receivables Sale occurs, any
charges or write-offs associated with the Globalstar Receivables or any gains
resulting from the Globalstar Receivables Sale in each case that are recorded or
taken after October 1, 2000, shall be disregarded for the purpose of calculating
Consolidated Interest Expense."

                  (iii) adding a proviso at the end of the definition of "Excess
Cash Flow" to read in its entirety as follows:

                  "provided that, if the Globalstar Receivables Sale occurs, any
cash received in connection with the Globalstar Receivables Sale, any charges or
write-offs associated with the Globalstar Receivables or any gains resulting
from the Globalstar Receivables Sale in each case that are recorded or taken
after October 1, 2000, shall be disregarded for the purpose of calculating
Excess Cash Flow."

                  (iv) adding a proviso at the end of the definition of
"Shareholders' Equity" to read in its entirety as follows:

                  "provided that, if the Globalstar Receivables Sale occurs, any
charges or write-offs associated with the Globalstar Receivables or any gains
resulting from the Globalstar Receivables Sale in each case that are recorded or
taken after October 1, 2000, shall be disregarded for the purpose of calculating
Shareholders' Equity."

                  (v) adding the following definition in the proper alphabetical
order:

                  "`Globalstar Receivables Sale': the sale, after the
declaration and payment of the $70,000,000 dividend by the Borrower contemplated
by Section 9.7, by the Borrower to Loral Space & Communications Corporation
(`LSCC') of receivables having a historical cost of at least $180,000,000 owed
by Globalstar L.P. to the Borrower for a purchase price equal to such historical
cost of such receivables (provided that at least $130,000,000 of the purchase
price is payable in cash and the remainder, if any, of such purchase price is
payable in the form of a promissory note issued by LSCC to the Borrower). The
Borrower shall provide notice of the completion of the Globalstar Receivables
Sale (which such notice shall evidence the occurrence thereof for purposes of
this Amendment) to the Administrative Agent and the Administrative Agent shall,
upon request by the Borrower, acknowledge the receipt of such notice and forward
such notice to the Lenders."
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                  Section 3. Amendment of Subsection 9.6 (Limitation on Sale of
Assets). Subsection 9.6 of the Credit Agreement is hereby amended by (i)
deleting the word "or" appearing at the end of paragraph (g) thereof and (ii)
deleting the period appearing at the end of paragraph (h) and adding in lieu
thereof the following:

                  "; or

                  (i)  the Globalstar Receivables Sale."

                  Section 4. Amendment of Subsection 9.8 (Limitation on
Investments, Loans and Advances). Subsection 9.8 of the Credit Agreement is
hereby amended by (i) deleting the word "and" appearing at the end of paragraph
(h) and (ii) deleting the period at the end of paragraph (i) and adding in lieu
thereof the following:

                  "; and

                  (j) the promissory note issued by the Parent in connection
with the Globalstar Receivables Sale."

                  Section 5. Amendment of Subsection 9.9 (Transactions with
Affiliates). Subsection 9.9 of the Credit Agreement is hereby amended by (i)
deleting the word "and" at the end of clause (a) and inserting a comma in lieu
thereof, (ii) deleting the word "and" at the end of clause (b) and inserting a
comma in lieu thereof and (iii) deleting the period at the end of clause (c) and
inserting in lieu thereof the following:

                  " and (d) the Globalstar Receivables Sale."

                  Section 6. Conditions Precedent. This Amendment shall become
effective as of the date hereof (the "Amendment Effective Date") upon receipt by
the Administrative Agent of counterparts of this Amendment, duly executed by the
Borrower, SS/L, and the Required Banks.

                  Section 7. Legal Obligation. The Borrower represents and
warrants to each Bank that the Credit Agreement and this Amendment constitute
legal, valid and binding obligations of the Borrower, enforceable against it in
accordance with their respective terms, subject to the effects of bankruptcy,
insolvency, fraudulent conveyances, reorganization, moratorium and other similar
laws relating to or affecting creditors' rights generally, general equitable
principles (whether considered in a proceeding in equity or at law) and an
implied covenant of good faith and fair dealing.

                  Section 8. Continuing Effect. Except for the amendments
expressly provided herein, the Credit Agreement shall continue to be, and shall
remain, in full force and effect in accordance with its terms. The amendments
provided herein shall be limited precisely as drafted and shall not be construed
to be an amendment or waiver of any other provision of the Credit Agreement
other than as specifically provided herein.

                  Section 9. Expenses. The Borrower agrees to pay or reimburse
the Administrative Agent for all of its reasonable out-of-pocket costs and
expenses incurred in connection with the development, preparation and execution
of, and any amendment, supplement or modification to, this Amendment and any
other documents prepared in connection herewith, and the consummation of the
transactions contemplated hereby and thereby, including, without limitation, the
reasonable fees and disbursements of counsel to the Administrative Agent.
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                  SECTION 10 GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND
OBLIGATIONS OF THE PARTIES UNDER THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.
<PAGE>   5
                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be duly executed and delivered by their proper and duly authorized
officers as of the date first above written.

                              LORAL SPACECOM CORPORATION


                              By:  /s/ Janet Yeung
                              Title: Vice President and Assistant Secretary


                              SPACE SYSTEMS/LORAL, INC.


                              By: /s/ Janet Yeung
                              Title: Vice President and Assistant Secretary


                              BANK OF AMERICA, NATIONAL ASSOCIATION,
                                as Administrative Agent, Issuing Bank and a Bank


                              By: /s/ Steve A. Aronowitz
                              Title: Managing Director


                              SAN PAOLO IMI S.p.A.,
                                as Selling Bank and in its individual capacity


                              By: ________________________________
                              Title:


                              By: ________________________________
                              Title:
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                                                     BANK OF MONTREAL


                                                     By:  /s/ Bruce A. Pietka
                                                     Title:  Director
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                                                     THE BANK OF NEW YORK


                                                     By:  /s/ Ken Sneider
                                                     Title: Vice President
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                                                     THE BANK OF NOVA SCOTIA


                                                     By:  /s/ Philip N Adsetts
                                                     Title:  Director
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                              BNP PARIBAS, formerly known as Banque Nationale de
                              Paris and successor to Paribas


                              By: /s/ Arnaud Collin du Bocage
                              Title: Director


                              By: /s/ Richard Pace
                              Title: Vice President, Corporate Banking Division
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                                                     BARCLAYS BANK PLC


                                                     By:  /s/ John Giannone
                                                     Title:  Director
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                                             BAYERISCHE LANDESBANK
                                             GIROZENTRALE CAYMAN ISLANDS
                                             BRANCH


                                             By: /s/ Hereward Drummund
                                             Title:  Senior Vice President


                                             By:  /s/ James H. Boyle
                                             Title:  Vice President
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                                                     THE CHASE MANHATTAN BANK


                                                     By:  /s/ William E. Rottino
                                                     Title:   Vice President
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                                                     CIBC INC.


                                                     By:  /s/ Michele E. Roller
                                                     Title:  Executive Director
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                                                     CITICORP USA, INC.


                                                     By:  /s/ Walter L. Larsen
                                                     Title:  Vice President
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                                             CREDIT LYONNAIS, NEW YORK BRANCH


                                             By:  /s/ Mark A. Campellone
                                             Title:   First Vice President
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                                             GE CAPITAL CORPORATION


                                             By:  /s/ Karl Kieffer
                                             Title:   Duly Authorized Signatory
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                                   THE INDUSTRIAL BANK OF JAPAN, LIMITED


                                   By:  /s/ Takuya Honjo
                                   Title:  Deputy General Manager
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                                             THE MITSUBISHI TRUST AND BANKING
                                             CORPORATION



                                             By:  /s/ Scott J. Paige
                                             Title:  Executive Vice President
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                                             PNC BANK, NATIONAL ASSOCIATION


                                             By:  /s/ Steffen W. Crowther
                                             Title:  Vice President
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                                         THE SANWA BANK, LIMITED



                                         By:  /s/ Stephen C. Small
                                         Title:  Senior Vice President and
                                                 Area Manager
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                                        THE SUMITOMO BANK LIMITED


                                        By:  /s/ Edward D. Henderson, Jr.
                                        Title:   Senior Vice President
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                                        THE TOKAI BANK, LIMITED

                                        NEW YORK BRANCH



                                        By:  /s/ Shinichi Nakatani
                                        Title:  Assistant General Manager
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                                   Schedule 1

         (1)      Globalstar vendor financing agreed upon in SS/L contract
                  number GF-C-94-0008, dated as of 2/16/1994 as amended (the
                  "Satellite Contract") in the principal amount of $110,105,000.
                  A portion of the Globalstar vendor financing was provided by
                  SS/L, as principal, and a portion was provided by
                  subcontractors (SS/L acts as the agent). As of 12/31/2000
                  $36,742,000 had been repaid.

         (2)      Globalstar vendor financing agreed upon in the Memorandum of
                  Understanding #5 dated 6/15/1995 (pursuant to the Satellite
                  Contract) in the principal amount of $90,000,000.

         (3)      Globalstar vendor financing agreed upon in the Memorandum of
                  Understanding #18 dated 9/9/1997 (pursuant to the Satellite
                  Contract) in the principal amount of $24,107,143. A portion of
                  the Globalstar vendor financing was provided by SS/L, as
                  principal, and a portion was provided by subcontractors (SS/L
                  acts as the agent). As of 12/31/2000 $8,045,143 had been
                  repaid.

         (4)      Orbital performance incentives as described in the Satellite
                  Contract and/or Memorandum of Understanding #18 referred to
                  above.

         (5)      Note from Globalstar dated June 30, 2000 in the principal
                  amount of $11,650,000 acquired pursuant to guaranty agreement
                  related to the Globalstar credit agreement with the The Chase
                  Manhattan Bank, N.A. dated 12/15/1995 as amended.

                       US$ IN THOUSANDS AS OF 12/31/2000
<TABLE>
<CAPTION>
AGREEMENT ITEM                                                                AMOUNT                  AMOUNT
                                                                                                    ASSIGNED
-------------------------------------------------------------------------------------------------------------
<S>                                                                <C>                          <C>

     1. Portion provided by SS/L as principal                            $    32,619              $    32,619
        Accrued interest on SS/L portion                                       3,536                    3,536
        Portion provided by subcontractors (SS/L acts as agent)               40,744                      -
        Accrued interest on subcontractor portion                              2,222                      -

     2. Portion provided by SS/L                                              90,000                   90,000
        Accrued interest on SS/L portion                                      42,416                   42,416

     3. Portion provided by SS/L as principal                                  7,031                    7,031
        Accrued interest on SS/L portion                                         773                      773
        Portion provided by subcontractors (SS/L acts as agent)                9,031                       -
        Accrued interest on subcontractor portion                                488                       -

     4. Remaining orbital performance incentives                               9,900                    9,900
        Accrued interest                                                          83                       83

     5. Outstanding Principal Amount                                          11,650                   11,650
        Accrued interest                                                         584                      584
                                                                          ----------                 --------
                                                                  TOTAL  $   251,077               $  198,592
</TABLE>