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


     This AMENDMENT TO AGREEMENT is made by and between MCI International,
Inc. ("MCI") and COMSAT Corporation ("COMSAT").

     WHEREAS, on January 24, 1994, MCI and COMSAT entered into an Agreement
for the provision of  telecommunications  services (the "1994  Agreement");
and

     WHEREAS,   the  1994   Agreement   was   submitted   to  the   Federal
Communications   Commission   ("FCC")   pursuant  to  Section  211  of  the
Communications Act; and

     WHEREAS,  the 1994  Agreement was amended as of July 1, 1995, and that
amendment was also submitted to the FCC; and

     WHEREAS, the Parties have again decided to amend the 1994 Agreement in
order to facilitate  COMSAT's  provision of  additional  telecommunications
services to MCI;

     NOW,  THEREFORE,  in  consideration of and in reliance upon the mutual
promises set forth below,  the Parties  hereby amend the 1994  Agreement as
follows;

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     1.   Article III of the Agreement, entitled "Base and Additional
Circuits," is revised by adding the following Paragraphs:

          H. In  addition  to the  Digital  Bearer  Circuits  described  in
     Paragraphs  A, B, C and G of this  Article,  COMSAT  hereby  agrees to
     provide,  and  MCI  commits  and  agrees  to  lease  from  COMSAT,  an
     additional  690  64-Kbps  equivalent  IDR Growth  Circuits,  provided,
     however that MCI may use New IBS Circuits  rather than IDR circuits to
     meet up to 52% (i.e., 360 circuits) of this commitment. The lease term
     for each of these 690 circuits shall commence as of August 1, 1996 and
     shall  run for a period  of ten  (10)  years.  The  rates,  terms  and
     conditions  for IDR  circuits  shall be as specified in Article IV and
     Attachments B and C, as amended herein, and for New IBS circuits shall
     be as  specified  in COMSAT FCC  Tariff  No. 1 except as  specifically
     modified by this Agreement.

          I. The  Parties  agree  that,  for those  circuits  described  in
     Paragraph H of this Article that may be activated as either IDR or New
     IBS circuits (i.e., up to 360 of the total of 690 circuits), MCI shall
     also have the  flexibility  to  exchange a New IBS  circuit for an IDR
     circuit of equivalent carrier size, and vice versa, at any time

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     during the 10-year lease term, at the rates applicable for the type of
     circuit  being  utilized.  "Equivalent  carrier  size"  means that the
     carrier(s)  taken down must have the same 64 Kbps circuit  capacity as
     the carrier(s) designated as replacements.

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

          F.  COMSAT's  rates  for Base and  Additional  Circuits  shall be
     reduced  as of July 1,  1996,  to the levels  that were  specified  in
     Attachments A, B, C, and D and were to take effect on January 1, 1997.

     3.   Article V of the Agreement, entitled "First Bulk Offering," is
revised by adding the following Paragraph L:

          L.  Consistent  with  Paragraph  H of this  Article,  the Parties
     hereby  agree that COMSAT shall  provide,  and that MCI shall place on
     the  INTELSAT  system  via  COMSAT,  Digital  Bearer  Growth  Circuits
     equivalent to an additional  10,000  Circuit  Months during the period
     from August 1, 1996 through December 31, 1997, and an additional 5,000
     Circuits  during the period from January 1, 1998 through  December 31,
     1998;

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     provided,  however,  that for purposes of this Paragraph only, MCI may
     use New IBS circuits rather than IDR circuits to meet up to 25% of its
     total  Circuit Month  commitment.  The Parties also affirm that COMSAT
     shall  provide  these 15,000  Circuit  Months to MCI on a  take-or-pay
     basis  at the  rate of $590  per  month  for  each 64 Kbps  equivalent
     circuit  (multiplied by the applicable rate adjustment factor, if any,
     as  specified  in  Attachment  B hereto  for IDR and as implied by the
     rates in Tariff F.C.C.  No. 1 for New IBS). For  accounting  purposes,
     unless  otherwise  instructed by MCI,  COMSAT will  attribute  Circuit
     Months ordered by MCI first to the offering made available  under this
     Paragraph and then to the offering made available  under  Paragraphs A
     through G of this Article in the original 1994 Agreement.

          M. COMSAT's  rates for the Circuit  Months made  available  under
     Paragraphs A through G of this Article  shall be reduced as of July 1,
     1996, to the levels that  otherwise  would have been  applicable as of
     January 1, 1997  pursuant to the  ratesetting  mechanism  set forth in
     Paragraph D and Attachment D in the original 1994 Agreement.

     4.   Article VI of the Agreement, entitled "Second Bulk Offering," is
revised by adding the following new paragraphs:

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          M. Consistent with the provisions of paragraph L of this Article,
     COMSAT  agrees to provide to MCI, and MCI agrees to lease from COMSAT,
     four  contiguous  segments of bandwidth in a high-power  (minimum 29.0
     dBW at beam edge) global beam transponder on the INTELSAT satellite at
     the 359 degree orbital location.  This allotment shall initially be in
     transponder  37/37. The first segment in this allotment shall be for 6
     MHz and was activated on July 14, 1996 for a one-year  lease term. The
     rate per month for this segment shall be $34,225 for the U.S. half. If
     MCI renews this segment for a succeeding  one-year  term, the rate per
     month shall be $51,337.50  for the U.S. half. The other three segments
     in this allotment shall be activated by October 27, 1997 for five-year
     lease  terms  and shall be for 3 MHz,  9 MHz and 18 MHz  respectively.
     During the first  twelve  months of service,  the  applicable  monthly
     rates for the U.S. half of these  segments shall be $14,205 for 3 MHz,
     $42,595 for 9 MHz, and $71,175 for 18 MHz. For the remaining 48 months
     of service,  the  applicable  monthly rates for the U.S. half of these
     segments  shall be  $21,307.50  for 3 MHz,  $63,892.50  for 9 MHz, and
     $106,762.50  for 18 MHz. If MCI elects to have COMSAT  self-match  any
     portion of this  capacity,  the above  rates shall be doubled for such
     self-matched portion.

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          N. Consistent with the provisions of paragraph L of this Article,
     COMSAT  also  agrees to provide  to MCI,  and MCI agrees to lease from
     COMSAT, two contiguous  segments of bandwidth in a high-power (minimum
     29.0  dBW at beam edge)  global  beam  transponder  at the 307 degrees
     orbital  location.  This allotment  shall  initially be in transponder
     37/37.  The first segment in this allotment shall be for 9 MHz and the
     second segment shall be for 3 MHz. The lease term for both segments of
     this allotment  shall be ten years;  the start dates for both segments
     shall be no later than August 1, 1997;  and the monthly  rates for the
     U.S. half of this allotment shall be $56,650 for the 9 MHz segment and
     $18,900 for the 3 MHz segment. If MCI elects to have COMSAT self-match
     any  portion of this  capacity,  the above  rates shall be doubled for
     such self-matched portion.

          O. Subject to the availability of capacity, MCI may incrementally
     activate  portions  (that are 9 MHz in  bandwidth  or  smaller) of the
     allotments described in paragraphs M and N of this Article at COMSAT's
     applicable tariffed VSAT rates prior to the stated start dates.

          P. The penalty for early termination of the allotments  described
     in  paragraphs  M and N of this  Article  (or  any  segment  of  those
     allotments)  shall be full payment for one-year  leases;  full payment
     for the first three  years of service  plus 75% of the balance due for
     five-year  leases;  and full payment

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     for the first  five  years plus 75% of the  balance  due for  ten-year
     leases.

          Q. The allotments described in paragraphs M and N of this Article
     shall be non-preemptible. In case of space segment failure, an attempt
     shall be made in  accordance  with  the  procedures  set  forth in the
     INTELSAT  Contingency  Plans,  as may be amended from time to time, to
     restore these allotments. These allotments may be used for any type of
     U.S. traffic, provided,  however, that: (1) INTELSAT's lease parameter
     definitions,  as set forth in the IESS and SSOG  documents that COMSAT
     routinely provides to MCI, shall apply to the use of these allotments;
     (2) COMSAT  and  INTELSAT  must  approve  transmission  plans for each
     circuit  located in the  allotments in advance of circuit  activation;
     and (3) these allotments may not absorb any other traffic  commitments
     that MCI has with COMSAT.

          R. The  Parties  recognize  that,  during  the lease  term of the
     allotments  described  in  paragraphs  M and N of  this  Article,  the
     particular  satellites on which service will initially be provided may
     be replaced by other  INTELSAT  satellites.  In that case,  COMSAT may
     substitute   other   high-power   (minimum  29.0  dBW  at  beam  edge)

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     transponders of the same  connectivity,  or, upon mutual  agreement of
     the  Parties,   a  transponder  of  different   connectivity   may  be
     substituted  for the  replaced  transponder  under the same  terms and
     conditions.  If high-power  transponder(s)  are not  available,  other
     transponder   capacity   may   be   substituted   for   the   replaced
     transponder(s) under rates, terms and conditions to be mutually agreed
     upon by the Parties.

          S.  The  Parties  agree  that  the  rates  and  other  terms  and
     conditions specified in paragraphs M, N, O, P, Q and R of this Article
     shall  supersede  any  conflicting  provisions in COMSAT World Systems
     Tariff F.C.C.  No. 1. All other terms and  conditions for the circuits
     contained in the  allotments  described in  paragraphs M and N of this
     Article  shall be the same as those  specified in COMSAT World Systems
     Tariff F.C.C.  No. 1 as of the effective date of this  Agreement,  and
     those tariff provisions are hereby incorporated into this Agreement.

     5.   Article VIII of the Agreement, entitled "Most Favored Carrier" is
revised by adding the following Paragraph E:

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          E. To the extent permitted by law, COMSAT agrees that, during the
     term of this Agreement,  it will offer MCI rates, terms and conditions
     for the bulk capacity made available pursuant to Paragraphs M and N of
     Article VI of this Agreement (i.e., a high-power global beam allotment
     at 359 degrees consisting  of four  contiguous  segments of  bandwidth
     comprising  6  MHz,  3 MHz,  9 MHz  and  18  MHz  respectively,  and a
     high-power  global  beam  allotment  at  307°E  consisting  of two
     contiguous   segments  of  bandwidth   comprising  9  MHz  and  3  MHz
     respectively)  that are no less  favorable  than the rates,  terms and
     conditions  it makes  available  to any  other  USISC  for  such  bulk
     capacity. In the event that, during the term of this Agreement, COMSAT
     makes available to another USISC rates,  terms and conditions for bulk
     capacity of the type made available  pursuant to Paragraphs M and N of
     Article  VI of this  Agreement  that are  more  favorable  than  those
     applicable under this Agreement, then such more favorable rates, terms
     and conditions  shall be offered to MCI in writing and, if accepted by
     MCI  in  writing,  shall  be  automatically   incorporated  into  this
     Agreement  as an amendment  thereto,  and shall be effective as of the
     date made available to such other USISC.

     6.   All other  provisions of the 1994 Agreement shall be interpreted in
a manner  consistent  with  this  Amendment,  but

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otherwise shall remain  unchanged and shall continue to have full force and
effect.

     7.   This Amendment to Agreement  shall become  effective 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.

MCI INTERNATIONAL, INC.               COMSAT CORPORATION



By: /s/ Anthony Cirieco               By: /s/ Robert S. Twining
    -----------------------------         ----------------------------------

                                             Vice President, Sales,
Title: Executive Director Finance     Title: Marketing and Business Planning
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Date: 9/17/96                         Date: September 16, 1996
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