AMENDMENT TO AGREEMENT
                          ----------------------

     This  AMENDMENT  TO AGREEMENT is entered into this 8th day of January,
1997 by and between AT&T Corp.  ("AT&T") and COMSAT Corporation  ("COMSAT")
(collectively referred to as the "Parties").

     WHEREAS,  on July 27, 1993,  AT&T and COMSAT entered into an Agreement
for the provision of  telecommunications  services (the "1993  Agreement");
and

     WHEREAS, on December 7, 1995, the 1993 Agreement was amended (the "1995
Amendment"); and

     WHEREAS,  both the 1993 Agreement and 1995 Amendment were submitted to
the Federal  Communications  Commission (the "FCC") pursuant to Section 211
of the Communications Act; and

     WHEREAS,  the Parties have decided to further amend the 1993 Agreement
in order to facilitate COMSAT's provision of additional  telecommunications
services to AT&T.

     NOW,  THEREFORE,  in  consideration of and in reliance upon the mutual
promises set forth below,  the Parties  hereby amend the 1993  Agreement as
follows:

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     1.   Article IV of the Agreement, entitled "Base and Additional
Circuits," is revised by adding the following Paragraph F:

          "F. The  Parties  agree that AT&T may  cancel  without  penalty a
     total  of up to 402 Base or  Additional  Circuits  prior to March  31,
     1997, provided, however, that: (1) billing for each of the 402 Base or
     Additional  Circuits  shall  cease as of the date that  AT&T  provides
     notice of  cancellation  and  identifies the circuit as one of the 402
     Base or Additional Circuits to be cancelled;  (2) AT&T shall extend by
     thirty-six  (36)  months  the  lease  terms  of at  least  660 Base or
     Additional Circuits that otherwise would have expired on June 30, 2000
     and up to 189 Base or Additional  Circuits that  otherwise  would have
     expired  between July 1, 2000 and December 31, 2000 for a total of 849
     Base or Additional  Circuits extended for thirty-six (36) months;  and
     (3) AT&T shall  identify  the 849 Base or  Additional  Circuits  whose
     leases are to be extended no later than March 31, 1997."

     2.   All other  provisions of the 1993  Agreement and the 1995 Amendment
shall  be  interpreted  in a  manner  consistent  with  this  Amendment  to
Agreement,  but otherwise shall remain unchanged and shall continue to have
full force and effect.

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     3.   This Amendment to Agreement  shall become  effective as of the date
executed   by  the   Parties   hereto,   upon   execution   by   authorized
representatives of both Parties, and shall be submitted to the FCC pursuant
to Section 211 of the Communications Act.

     IN WITNESS  WHEREOF,  each of the  Parties  hereto has  executed  this
Amendment to Agreement.


AT&T CORP.                              COMSAT CORPORATION

By: /s/ C. A. Peters                    By: /s/ John H. Mattingly
    -------------------------------         ---------------------

Name:   C. A. Peters                    Name:   John H. Mattingly
     ------------------------------          --------------------

Title: Supplier Management Director     Title: Vice President and
       ----------------------------            General Manager
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