EXHIBIT 99
[VASTAR LETTERHEAD]
                                                       NR00-11

                                                       April 18, 2000

FOR IMMEDIATE RELEASE
VASTAR'S BOARD OF DIRECTORS ELECTS CHARLES D. DAVIDSON AS CHAIRMAN FOLLOWING
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RESIGNATION OF FOUR ARCO EXECUTIVES FROM ITS BOARD
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Houston, TX -- Vastar Resources, Inc. (NYSE: VRI) today announced the election
of Vastar's president and chief executive officer, Charles D. Davidson, to the
additional position of chairman of the board following the resignation of four
board members who were executives of Atlantic Richfield Company (ARCO).  The
election and resignations followed the merger of ARCO and Prairie Holdings,
Inc., a subsidiary of BP Amoco Corporation, as a result of which BP Amoco gained
indirect ownership of approximately 81.9 percent of Vastar's common stock.

     Resigning from the board were Michael E. Wiley, chairman; Terry G. Dallas,
Marie L. Knowles and Donald R. Voelte Jr., who were all ARCO executives.

     "We sincerely thank the departing board members for the significant
contributions they have made to Vastar's success," said Davidson.  "In
particular, I thank Mike Wiley for the leadership he displayed while serving as
president and chief executive officer during Vastar's first three years, and as
our chairman since 1996.  His guidance has been invaluable to our company.

     "Under the stewardship of these directors, Vastar has become one of the
best-performing companies in the independent E&P sector.  Our


shareholders have recognized this performance, and we appreciate their ongoing
support," Davidson added.

     Continuing on the board with Davidson are Steven J. Shapiro, Vastar's
senior vice president and chief financial officer; and independent directors
J. D. Callison, retired vice president of Schlumberger Limited; Robert C.
LeVine, retired managing director of J. P. Morgan Investment Management, Inc.;
and William D. Schulte, retired vice chairman of KPMG, LLP. BP Amoco did not
submit candidates for board election.

     Messrs. Callison, LeVine and Schulte currently serve on a special committee
engaged in evaluating BP Amoco's proposal to acquire for $71 per share the
18.1 percent of Vastar's stock that is currently publicly traded.

  Vastar Resources, Inc., headquartered in Houston, Texas, finds, develops and
produces natural gas and liquid hydrocarbons.  The company is active in more
than 100 producing fields, with exploration and production activities in the
Gulf of Mexico shelf and deepwater, Gulf Coast, Rocky Mountains and Mid-
Continent areas.  BP Amoco owns indirectly approximately 81.9 percent of
Vastar's common stock.  Additional information on Vastar is available on the
company's website at www.vastar.com.

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Contacts:    James Bartlett  (281) 584-3448 (media)
             Ellen DeSanctis (281) 584-3477 (financial)


Except for the historical information contained herein, the matters discussed in
this press release are forward-looking statements that involve certain
assumptions, risks and uncertainties which, in the event actual results were
different from those predicted by the company, could negatively impact future
results, plans and expectations.  Actual results could differ materially from
expectations based upon numerous factors, including: (i) the

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volatility and level of hydrocarbon commodity prices, (ii) lower than expected
production rates due to capacity restraints on pipeline systems, other
infrastructure or other reasons, (iii) the inexact nature of reserve estimates,
(iv) the legal and/or regulatory environment, (v) drilling and operating risks,
(vi) competition, (vii) certain natural gas marketing matters and (viii) the
outcome of the proposed acquisition transaction relating to the company's
publicly-owned common stock as previously announced by BP Amoco p.l.c. Further
details with respect to some of the above as well as other assumptions, risks
and uncertainties are detailed from time to time in our reports filed with the
Securities and Exchange Commission, including the material on pages 12-14 in the
company's Report on Form 10-K for the year ended December 31, 1999.

As previously announced on March 16, 2000, BP Amoco advised Vastar's board of
its intention to commence a tender offer for the minority stockholding of the
company.  Vastar shareholders are strongly advised to read both the tender offer
statement and the solicitation/recommendation statement regarding the tender
offer when they become available, as these statements will contain important
information relating to the tender offer. Shareholders will be able to obtain
these statements and any amendments thereto and other filed documents for free
at the Internet website maintained by the Securities and Exchange Commission at
www.sec.gov. In addition, Vastar Resources, Inc. will make the
solicitation/recommendation statement and any amendments thereto available for
free to Vastar's shareholders. Please direct your request for the
solicitation/recommendation statement to Ellen DeSanctis, Manager of Investor
Relations and Corporate Communications, Vastar Resources, Inc., 15375 Memorial
Drive, Houston, Texas 77079, Telephone (281) 584-3477.

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