Exhibit 10.25.1
                              


                                                                  EXECUTION COPY

                                    AMENDMENT

     This  Amendment  (the  "Amendment")  is entered  into as of this 5th day of
March,  1998, by and between PanAmSat  International  Systems,  Inc., a Delaware
corporation,  formerly known as PanAmSat Corporation  ("PanAmSat") and Televisa,
S.A. de C.V., a sociedad Anonima de Capital  Variable,  formed under the laws of
the United  Mexican  States  ("Customer").  This  Amendment  amends that certain
"Full-Time Transponder Service Agreement from PAS-3 (European Beam)" dated as of
September 20, 1996, by and between the parties  hereto (the  "Agreement").  This
Amendment  is being  entered  contemporaneously  with that  certain  Transponder
Service  Agreement  by and  between  PanAmSat  and Sky  Multi-Country  Partners,
previously  referenced  as  Multi-Country  Partners,  GP  ("Multi-Country,"  the
"Multi-Country Agreement").

                                 MATTERS AMENDED

     In  consideration  of the  foregoing  and of the mutual  promises set forth
below, and for other valuable  consideration,  the receipt and adequacy of which
is hereby acknowledged,  PanAmSat and Customer mutually agree that the following
provisions  of the  Agreement  are  amended or added,  as  applicable.  Sections
referenced  correspond  to  the  Agreement  and  replace  the  Sections  of  the
corresponding numbers (if any) in the Agreement:

     1.2  Beam and Transponder  Designation.  The Beams,  and subject to Section
5.3 and Appendix C, the  particular  Transponders  upon which  Customer shall be
provided  Service (the  "Service  Transponders")  are shown in Appendix A. It is
hereby acknowledged that through October 31, 1997, the Service Transponders were
the following three (3) Transponders: 7, 11, and 15 (all Europe downlink Beams),
and that,  effective  as of November  1, 1997,  the  Service  Transponders  were
changed to the following five (5) Ku-band  Transponders:  6, 10, 11, 13, and 14.
At Customer's  request,  Transponders 6, 10, 13, and 14 have or will be switched
into the NSA or SSA downlink Beams of PAS-3 to accommodate  the  requirements of
Multi-Country.  In addition,  in circumstances  under which  Multi-Country would
have the right to have the uplink Beam  changed if the same Service was supplied
to it by PanAmSat  under the  Multi-Country  Agreement,  at  Customer's  request
(based upon  Multi-Country's  request to it) the uplink Beam will be changed for
the applicable  Transponder(s).  When Multi-Country is no longer entitled to the
use of these Transponders  under its sublease agreement with Televisa,  Televisa
shall  so  notify   PanAmSat  (the  "End  of  the   Multi-Country Availability  


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Requirement"),  and these  Transponders  will be switched to the Europe or North
America downlink Beams, as applicable, and, if applicable, the uplink Beams back
to the Europe/North America Beam.

     The foregoing notwithstanding,  at Customer's request, PanAmSat shall leave
the Transponders in the configuration  established for  Multi-Country  under the
preceding  paragraph,  provided  that:  (a)  such  configuration  shall  only be
permitted to be used for the  transmission  of "Customer's  Television  Service"
with the definition of "Commonly Controlled Entities" (other than Multi-Country)
limited to entities in which there is a minimum of 50.1% common equity ownership
with Customer;  and (b) PanAmSat may require the  Transponders to be switched to
the  configuration  shown in Appendix A (without regard to the footnotes) at any
time on notice to Customer if such a switch is necessary to allow the use of the
frequencies by another satellite without  interference to or from that satellite
(or its use), at PanAmSat's  desired location of use. The restrictions set forth
in this paragraph  shall not apply,  and Customer's use of the  Transponders  as
configured for the benefit of  Multi-Country  shall be subject to the other more
general  provisions  of  this  Amendment  and  the  Agreement,  if  PanAmSat  is
technically unable to switch the Transponders back to the configuration shown in
Appendix A (without  regard to the  footnotes)  at the End of the  Multi-Country
Availability  Requirement;  provided that,  within sixty (60) days of PanAmSat's
determination that such Transponder(s)  cannot be switched,  PanAmSat shall have
the right,  on notice to Customer to terminate  this Agreement as to one or more
of such unswitchable Transponders.

     No other  switching of downlink  Beams (or uplink beams) shall be permitted
without  PanAmSat's  express written consent.  All changes of downlink Beams are
subject to the following additional requirements:

               (a)  If  the  change  cannot  be  accomplished  using  reasonable
engineering standards, this Agreement shall continue to operate with the Service
Transponders  in their  then-existing  configuration  without  the  contemplated
change;

               (b)  If  the  change  was  expressly   authorized  by  the  first
paragraph of this Section 1.2 (i.e.,  as to the downlink  Beams to NSA or SSA to
accommodate  Multi-Country  and back to Europe or North  America  when no longer
needed for Multi-Country, or, if applicable, as to the change of uplink Beams to
accommodate  Multi-


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Country if it would be permitted under the Multi-Country Agreement and back to
the Europe/North America uplink Beam when no longer required by Multi-Country),

               Then, as to a change of downlink  Beams,  PanAmSat shall bear the
risk of loss if the  Service  Transponder(s)  is damaged or made  unusable  as a
result of attempting to make such change  (i.e.,  if the Service  Specifications
for such Transponder can no longer be met in any  configuration,  the provisions
of this  Agreement  that  apply  to a  failure  of a  Service  Transponder  on a
Confirmed Basis shall apply) and, as to a change of uplink Beams, PanAmSat shall
bear such risk if it would have had such risk if the Service  had been  supplied
by it to Multi-Country under the Multi-Country Agreement; and

               (c)  Except as provided in the preceding clause (b), Customer
shall  accept  the risk of loss if a Service  Transponder(s)  is damaged or made
unusable as a result of attempting to make any further  switch to which PanAmSat
may consent (i.e., the Service Transponder shall not be deemed to have failed on
a Confirmed Basis).

          1.2A. Beam Election. Implemented.



          1.3A Additional Use  Restrictions.  Customer  acknowledges  and agrees
that, notwithstanding anything in this Agreement to the contrary, its use of any
Transponder  in the SSA, NSA, or North America  downlink Beams of PAS-3 (and all
uses that may be permitted under this Agreement)  shall be subject to all of the
[*******************************************************************************
********************************************************************************
********************************************************************************
**************************************].

          1.5 Interim Marketing of the Capacity.

              (a) If neither  Customer  nor  Multi-Country  requires  all of the
capacity provided  hereunder,  until the End of the  Multi-Country  Availability
Requirement,  upon Customer's request, PanAmSat shall use all reasonable efforts
to market  services  for  occasional  use from the Service  Transponders  (which
Customer  would  thereafter  cease to employ) on a rolling sixty (60) day cycle,
subject to recall by Customer on  sixty-five  (65) days'  notice (but subject to
preemption  on  twenty-four  (24)  hours  notice if  required  by  


[***]     Filed separately with the Commission pursuant to a request for 
          confidential treatment.


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Customer  for
Multi-Country  [******************************************]  to other  potential
customers  for video,  data,  or other  uses,  as market  demand  and  technical
considerations may warrant, as reasonably determined by PanAmSat in consultation
with Customer,  and subject to PanAmSat's  reasonable  discretion with regard to
the terms and  conditions  of service and  selection of  appropriate  customers,
which shall be  consistent  with its general  practices in this regard.  In such
event,  PanAmSat shall credit against Customer's next monthly Service Fee (which
shall  continue  to be  payable)  [*********************************************
********************************************************************************
********************************************************************************
******************************************************************] In addition,
after deducting [*******] specified  above, if the monthly service fees actually
received  by  PanAmSat  for service  from the  Service  Transponders  exceed the
monthly  Service  Fees to be paid to  PanAmSat by  Customer  for the  remarketed
capacity (the "Excess Amount") in addition to crediting the next month's Service
Fee payment, [*****************************************************].

          1.6 Additional Marketing of Excess Capacity.

              (a) At  Customer's  written  request (an  "Availability  Notice"),
which may be given at any time after the End of the  Multi-Country  Availability
Requirement,  PanAmSat shall use all reasonable  efforts to market services from
one or more of the Service  Transponders (which Customer would thereafter,  on a
minimum of thirty (30) days'  notice  from  PanAmSat,  or such lesser  period of
notice  as  Customer  may  agree  in  writing,  cease  to  employ),  as shall be
designated  in  the  Availability  Notice  to  other  potential  customers  on a
full-time,  full  transponder  basis for video,  data,  or other uses, as market
demand and technical  considerations  may warrant,  as reasonably  determined by
PanAmSat in  consultation  with Customer,  and subject to PanAmSat's  reasonable
discretion  with regard to the terms and  conditions of service and selection of
appropriate  customers,  which shall be consistent with its general practices in
this regard. In such event,

                    (i) PanAmSat shall actively market services from the Service
Transponders  in good faith provided that PanAmSat shall not be obligated to use
the 


[***]     Filed separately with the Commission pursuant to a request for 
          confidential treatment.


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Service  Transponders  ahead of any other  capacity  that PanAmSat may also have
available for comparable service.  Unless otherwise agreed by both parties,  the
marketing shall be for full-time,  fixed term uses. In addition,  subject to the
considerations  stated  above,  if Customer  identifies  to PanAmSat a potential
customer who desires to purchase  service from PanAmSat that employs the Service
Transponders,  PanAmSat  shall  seek,  in good  faith,  promptly to enter into a
service  agreement with said customer,  provided that if PanAmSat was already in
negotiations with said potential customer for other PanAmSat capacity,  PanAmSat
shall not be required to discontinue such negotiations; and

                    (ii) PanAmSat shall credit against  Customer's  next monthly
Service Fee (which shall  continue to be payable) [*****************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
**********************] In addition,  after deducting [*******] specified above,
if the monthly  Service Fees actually  received by PanAmSat for service from the
Service  Transponders  exceed the monthly Service Fees to be paid to PanAmSat by
Customer  for the  remarketed  capacity  (the  "Excess  Amount")  in addition to
crediting  the next  month's  Service Fee payment,  [***************************
*************************************]

              (b) At any time  that is six  months  or more  after the date that
Customer shall have given an unwithdrawn  Availability Notice, Customer shall be
permitted  on notice to  PanAmSat  to  replace  an  Availability  Notice  with a
"Sublease Notice" as to such Service Transponder(s) that had been subject to the
Availability  Notice.  Upon  giving of such a notice,  subject  to any  customer
agreements  that  PanAmSat  may  have  entered  under  and  consistent  with the
Availability  Notice,  Customer  shall be  permitted  to sublease  such  Service
Transponder  capacity itself to third parties on a full-time,  full  transponder
basis, subject to the following conditions:

              (i) Any such sublease shall be subject to PanAmSat's prior written
consent;  provided  that such  consent  shall not be  unreasonably  withheld  or
delayed,  it being  understood  that  PanAmSat may withhold its consent only if:


[***]     Filed separately with the Commission pursuant to a request for
          confidential treatment.
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(A) PanAmSat  determines  in good  faith,  that  some  or all of the  sublease's
programming  (information  about which  Customer  shall provide to PanAmSat upon
PanAmSat's  request)  may  be  pornographic,  involve  religious  fanaticism  or
political  advocacy,  obscene,  indecent,  slanderous,  or in  violation  of any
governmental programming restrictions;  or (B) PanAmSat was demonstrably already
engaged  in  marketing  other  PanAmSat   capacity  with   comparable   coverage
("Comparable Capacity") to the required sublessee(s),  evidence of which (which,
if in writing,  may be excised to protect proprietary  information and, if oral,
will be  summarized  by  PanAmSat)  shall be provided to Customer by PanAmSat at
Customer's written request;

              (ii) Any  marketing by Customer to potential  sublessees  shall be
only  via  "soft   marketing,"  i.e.,   one-to-one,   private  and  confidential
discussions  with  third  parties  and  shall  not  include  any  public or mass
marketing of such capacity,  or employ the use of brochures or similar materials
intended for broad distribution.  If Customer is informed (either by PanAmSat or
by a potential sublessee) that the sublessee is in negotiation with PanAmSat for
Comparable  Capacity,  Customer shall discontinue its marketing efforts directed
at such sublessee);

              (iii) Customer:  (A) shall remain responsible directly to PanAmSat
for compliance with all obligations under this Agreement, including payment; (B)
shall be responsible  for and shall require its sublessees to comply with all of
the conditions of use  (operational  and content) of this Agreement;  and (C) if
any sublessee will have an uplink to the Satellite that is not under  Customer's
direct  operational  control,  shall require said  sublessee(s)  to enter into a
third party access  agreement(s)  with  PanAmSat,  which makes said  sublessee's
obligations  to comply with the conditions of use  (operational  and content) of
this  Agreement  enforceable  directly by PanAmSat  against such third party (as
well as against Customer); and

              (iv) Customer shall notify PanAmSat of all consideration  promised
and/or received by its sublessees.  In the event that such consideration exceeds
the amount of (A) Customer's Service Fee for the applicable Service  Transponder
and for the same  period  of use;  and (B) such  costs  reasonably  incurred  by
Customer for providing any related services and equipment to said sublessee, not
provided by PanAmSat, that may be associated with the provision of such service,
e.g., turnaround, compression, or other terrestrial services of facilities or in
subleasing the Service  Transponder or in remarketing such capacity (the "Excess
Amount"),  then, in addition to the monthly  


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Service  Fees  to  be  paid  to  PanAmSat  by  Customer,   Customer   shall  pay
[********************************************************] to PanAmSat.

          (c)  Subject to any third party  agreements  which  PanAmSat  may have
entered while the Service  Transponder(s) are made available to it under Section
1.6(a) above consistent with the Notice of Availability that was given, Customer
may withdraw an  Availability  or Sublease  Notice at any time;  provided  that,
until withdrawn,  PanAmSat may, on notice to Customer,  terminate this Agreement
as to one or more of the  Service  Transponders  that  are  then  subject  to an
Availability  or Sublease  Notice,  subject to any sublease  agreements to which
PanAmSat may have consented pursuant to Section 1.6(b) above.

     2.2 (b) The Service  Term for the  remaining  two (2) Service  Transponders
(the "Remaining Two"), and the change of designation of two of the three Initial
Group Transponders,  is acknowledged to have commenced on November 1, 1997. (For
the  avoidance  of doubt,  there is no change to  clauses  (a) or (c) of Section
2.2.)

     Appendix A, Transponder  Designations.  A revised Appendix A is attached to
this Amendment.

     Appendix   B,   Service   Specifications.   In   addition  to  the  Service
Specifications  that  are  (and  remain,  where  applicable)  part of the  PAS-3
Agreement,  Service  Specifications  associated  with  the  use of  the  Service
Transponders  when  switched  into the SSA or NSA  beams  are  attached  to this
Amendment. [same as used for MultiCountry PAS-3 specs]


[***]     Filed separately with the Commission pursuant to a request for 
          confidential treatment.


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     Each of the parties has duly  executed and delivered  this  Amendment as of
the day and year first written above.

                  PANAMSAT INTERNATIONAL SYSTEMS, INC.


                  By:                                                           
                  Name:                                                         
                  Title:                                                        



                  TELEVISA, S.A. de C.V.


                  By:                                                           
                  Name:                                                         
                  Title:                                                        



<PAGE>



                                                            APPENDIX A (REVISED)


                              SERVICE TRANSPONDERS

                                      PAS-3


             INITIAL GROUP (March 1, 1997 through October 31, 1997)

                           UPLINK                        DOWNLINK
Transponder #    MHz    Band     Beam                 Band       Beam

7-EK             64     Ku       Eur/No. Amer V        Ku        Europe H
11-EK            54     Ku       Eur/No. Amer V        Ku        Europe V
15-EK            54     Ku       Eur/No. Amer V        Ku        Europe V

              FIVE TRANSPONDERS (November 1, 1997, and thereafter)
11-EK            54     Ku       Eur/No. Amer V        Ku        Europe V
13-K             54     Ku       Eur/No. Amer V        Ku        Europe V*
 6-K             54     Ku       Eur/No. Amer H        Ku        No. Amer V**
10-K             54     Ku       Eur/No. Amer H        Ku        No. Amer V**
14-K             54     Ku       Eur/No. Amer H        Ku        No. Amer V**



                           

*   To be switched to NSA Beam for Multi-Country and then back to Europe.

**  To be switched to SSA Beam for Multi-Country and then back to No. Amer.