EXHIBIT 99.6


     GUARANTEE,  dated as of December  15,  1994,  made by Viacom  International
Inc., a Delaware  corporation (the "Guarantor"),  in favor of the holders of the
8% Exchangeable  Subordinated  Debentures (the  "Debentures") due 2006 of Viacom
Inc. ("Viacom").

                                  WITNESSETH:
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     SECTION 1. Guarantee.  The Guarantor hereby unconditionally  guarantees the
punctual  payment  when due,  whether at stated  maturity,  by  acceleration  or
otherwise,  of the principal of, premium, if any, and interest on the Debentures
(the  "Obligations"),  according  to the terms of such D tures and as more fully
described in the Indenture  dated as of July 1, 1994,  between Viacom and Harris
Trust and Savings  Bank (the  "Trustee"),  as trustee (as  amended,  modified or
otherwise   supplemented   from  time  to  time,   referred  to  herein  as  the
"Indenture").

     SECTION  2.  Guarantee   Absolute.   The  Guarantor   guarantees  that  the
Obligations will be paid strictly in accordance with the terms of the Indenture,
regardless  of any law,  regulation  or order now or  hereafter in effect in any
jurisdiction  affecting  any of  such  terms  or the  rights  of  holder  of the
Debentures  with respect  thereto.  The  liability of the  Guarantor  under this
Guarantee shall be absolute and unconditional irrespective of::

     (i) any lack of validity or  enforceability  of any of the Indenture or any
other agreement or instrument relating thereto;

    (ii) any change in the time, manner or place of payment of, or in any other
term of, all or any of the  Obligations,  or any other amendment or waiver of or
any consent to departure from any of the Indenture;

   (iii) any exchange,  release or  non-perfection  of any collateral,  or any
release  or  amendment  or  waiver of or  consent  to  departure  from any other
guaranty, for all or any of the Obligations; or

    (iv) any other  circumstance  which might  otherwise  constitute  a defense
available to, or a discharge of, Viacom, or a guarantor.

     SECTION 3. Waiver.  The  Guarantor  hereby waives  diligence,  presentment,
demand  of  payment,  filing  of  claims  with a court in the event of merger or
bankruptcy  of Viacom,  any right to require a  proceeding  filed first  against
Viacom,  protest  or notice  with  respect  to the  Debentures  or  indebtedness
evidenced thereby and all demands whatsoever.



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     SECTION 4. No Waiver; Remedies. No failure on the part of any holder of the
Debentures to exercise,  and no delay in exercising,  any right  hereunder shall
operate as a waiver  thereof;  nor shall any single or partial  exercise  of any
right  hereunder  preclude  any other or further exer thereof or the exercise of
any other right.  The remedies  herein provided are cumulative and not exclusive
of any remedies provided by law.

     SECTION 5. Continuing Guarantee;  Transfer of Interest. This Guarantee is a
continuing  guaranty  and shall (i) remain in full  force and  effect  until the
earliest to occur of (A) the date on which the Guarantor shall  consolidate with
or merge into Viacom or any successor  thereto,  (B) date on which Viacom or any
successor  thereto  shall  consolidate  with or merge into the Guarantor and (C)
payment in full of the  Obligations,  (ii) be binding  upon the  Guarantor,  its
successors and assigns,  and (iii) inure to the benefit of and be enforceable by
any holder of Debentures,  by th e Trustee, and by their respective  successors,
transferees, and assigns.

     SECTION  6.  Subordination.  The  payment  of the  Obligations  under  this
Guarantee is hereby expressly subordinated to (a) the 9-1/8% Senior Subordinated
Notes due 1999 of the Guarantor, 8-3/4% Senior Subordinated Reset Notes due 2001
of the Guarantor and 10-1/4%  Senior  Subordinated  No due 2001 of the Guarantor
(collectively,  the "VII Indebtedness") issued under the Indenture,  dated as of
September 15, 1991, among the Guarantor,  as issuer, Viacom Inc. ("Viacom"),  as
guarantor, and The Bank of New York ("BONY"), as trustee, as supplemented by the
First Supplemental Indenture dated as of September 15, 1991 among the Guarantor,
Viacom  and  BONY,  and  as  further  supplemented  by the  Second  Supplemental
Indenture  dated  as of March 4,  1992  among  the  Guarantor,  Viacom  and BONY
(collectively,  the "VII Indenture"),  (b) the Senior Indebtedness (as such term
is  defined  in  the  VII  Indenture)  of  the  Guarantor  to  which  such  VII
Indebtedness  is  subordinated  and (c) the Senior  Obligations (as such term is
defined in the Indenture as if such term, and the terms referred to therein, are
applied to the Guarantor) of the Guarantor.

     SECTION 7. Reinstatement.  This Guarantee shall continue to be effective or
be  reinstated,  as the case may be,  if at any time any  payment  of any of the
Obligations  is  rescinded  or must  otherwise  be returned by any holder of the
Debentures  or the Trustee upon the  insolvency,  bankrup or  reorganization  of
Viacom or otherwise, all as though such payment had not been made.

     SECTION 8. Limitation of Guarantor's Liability.  The Guarantor,  and by its
acceptance of this Guarantee each holder of Debentures,  hereby confirms that it
is the intention of all such parties that in no event shall any  obligations  of
the Guarantor  under its Guarantee  constitute a f ulent  transfer or conveyance
for  purposes  of, or result in a  violation  of, any United  States  federal or
applicable  United States state law. To effectuate the foregoing  intention,  in


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the event that this Guarantee would, but for this sentence, constitute or result
in such a transfer or violati on, then the liability of the Guarantor  under its
Guarantee  shall be reduced to the extent  necessary to eliminate such violation
under the applicable fraudulent conveyance or similar law.

     SECTION 9.  Amendment.  The Guarantor may amend this  Guarantee at any time
for any  purpose  without  the  consent  of the  Trustee  or any  holder  of the
Debentures.

     SECTION  10.  Governing  Law.  THIS  GUARANTEE  SHALL BE  GOVERNED  BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK,  WITHOUT REGARD
TO THE PROVISIONS THEREOF RELATING TO CONFLICT OF LAWS.

     IN WITNESS  WHEREOF,  the  Guarantor  has caused this  Guarantee to be duly
executed and delivered by its officer  thereunto duly  authorized as of the date
first above written.

                                        VIACOM INTERNATIONAL INC.


                                        By: /s/ GEORGE S. SMITH, JR.
                                           ------------------------------------
                                           Name:  George S. Smith, Jr.
                                           Title: Senior Vice President,
                                                  Chief Financial Officer