EXHIBIT 20

FOR IMMEDIATE RELEASE                        Contact: Greg Wright
                                                    (210)283-2440

                                  News Release


                         TESORO ANNOUNCES EXTENSION OF
                            STOCKHOLDER RIGHTS PLAN


     San Antonio,  Texas  --  Dec.  18,  1995  --  Tesoro  Petroleum Corporation
(NYSE:TSO) today announced its board of directors elected on Dec. 15  to  extend
the  company's  stockholder rights plan, which  was scheduled to expire Dec. 16.
The board voted to change the plan's expiration date to the close of business on
July 24, 1996.
     The stockholder rights plan  was  extended  to  allow the board to consider
whether  the  plan  remains  appropriate  to  continue  ensuring   that   Tesoro
shareholders would receive fair and equal treatment in the event of any proposed
takeover  of  the  company.   The  extension was not in response to any specific
effort to acquire control of the company.

     Tesoro Petroleum  Corporation  is  a  natural  resource  company engaged in
petroleum refining and marketing, natural gas exploration  and  production,  and
wholesale marketing of fuel and lubricants.

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