EXHIBIT 99.11
 
  AMENDMENT TO VIACOM GUARANTEE (this "Amendment to Guarantee") dated as of
July 22, 1996, to be effective as of July 31, 1996 by VIACOM INC., a Delaware
corporation (the "Guarantor").
 
                             W I T N E S S E T H :
 
  WHEREAS, the Guarantor is the guarantor under a Guarantee dated as of
December 15, 1994 (the "Guarantee") in favor of the holders of the 7 1/2%
Senior Notes due 2002, 8 1/4% Senior Notes due 2022, 5 7/8% Senior Notes due
2000 and 7 1/2% Senior Notes due 2023 (collectively, the "Securities") of
Viacom International Inc., a Delaware corporation (the "Assignor") (as
successor to Paramount Communications Inc.);
 
  WHEREAS, the Assignor and Viacom International Services Inc., a Delaware
corporation (the "Assignee") are parties to an Implementation Agreement dated
as of July 24, 1995 (the "Implementation Agreement") pursuant to which,
subject to the terms and conditions stated therein, the Assignor shall convey
substantially all of its assets to the Assignee (the "Conveyance of Assets")
and the Assignee shall assume substantially all of the liabilities of the
Assignor (the "Assumption of Liabilities");
 
  WHEREAS, under a Supplemental Indenture (the "Supplemental Indenture"), of
even date herewith, among the Assignor, the Assignee and The Bank of New York,
Trustee, the Assignor shall assign its obligations under the Securities to the
Assignee;
 
  WHEREAS, the Guarantor anticipates that shortly after the consummation of
the Conveyance of Assets and the Assumption of Liabilities, the Assignor shall
change its name to TCI Pacific Communications Inc. and the Assignee shall
change its name to Viacom International Inc.;
 
  WHEREAS, the Guarantor will derive substantial direct and indirect benefits
from the transactions contemplated by the Implementation Agreement and the
other agreements contemplated thereby; and
 
  WHEREAS, effective upon the Assumption of Liabilities by the Assignee, the
Guarantor desires to amend the Guarantee as herein provided.
 
  NOW, THEREFORE, in consideration of the premises herein contained, the
Guarantor hereby agrees as follows:
 
  1. The Guarantor hereby irrevocably reaffirms all of the rights and
obligations of the Guarantor under the Guarantee, and the Guarantor agrees to
perform and to be bound by all of the terms, covenants and conditions of the
Guarantee which were binding upon, and to be kept, observed or performed by it
prior to the execution of the Supplemental Indenture.
 
  2. The reaffirmation hereunder of the Guarantee shall become effective
concurrently with the Conveyance of Assets and the Assumption of Liabilities
in accordance with the Implementation Agreement.
 
  3. In furtherance of the foregoing, from and after the date of this
Amendment, the Guarantee is hereby amended so that all references therein to
"Paramount Communications Inc." or "Paramount" are hereby deemed to be
references to "Viacom International Services Inc.", until such time as the
Assignee changes its name to "Viacom International Inc.", from which time all
references to "Paramount Communications Inc." and "Paramount" shall be deemed
to be references to the Assignee and any successor thereto.
 
  4. On and after the date hereof, each reference in the Guarantee to "this
Guarantee", "hereunder", "hereof" or words of like import referring to the
Guarantee, shall mean and be a reference to the Guarantee as amended hereby.
 
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  5. Except as specifically provided by this Amendment to Guarantee, the
Guarantee is and shall continue to be in full force and effect and is hereby
in all respects ratified and confirmed.
 
  6. THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THIS AMENDMENT TO
GUARANTEE.
 
  IN WITNESS WHEREOF, the Guarantor has caused this Amendment to Guarantee to
be duly executed as of the date first above written.
 
 
                                          VIACOM INC.
 
                                            /s/ Vaughn Clarke
                                          By___________________________________
                                            Name: Title:
 
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