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                                                               EXHIBIT (a)(1)(U)


           SHELL EXTENDS BARRETT TENDER OFFER FOR ADDITIONAL TWO WEEKS


         HOUSTON (APRIL 20, 2001) - Shell Oil Company (Shell) today extended its
tender offer for all outstanding shares of Barrett Resources Corporation (NYSE:
BRR) to 12:00 midnight, EDT, on May 4, 2001.

         As of the close of the market on April 19, 2001, 155,420 shares of
Barrett stock had been tendered into Shell's offer. Shell Oil Company is a
wholly-owned member of the Royal Dutch/Shell Group (NYSE: RD, SC).

                                   **********

SHELL OIL COMPANY HAS FILED A PRELIMINARY CONSENT STATEMENT AND OTHER
SOLICITATION MATERIALS WITH THE SEC RELATING TO SHELL OIL COMPANY'S SOLICITATION
OF WRITTEN CONSENTS FROM THE SHAREHOLDERS OF BARRETT RESOURCES CORPORATION.
INVESTORS AND SECURITY HOLDERS ARE STRONGLY ADVISED TO READ THE DEFINITIVE
CONSENT STATEMENT, WHEN AVAILABLE, BECAUSE IT WILL CONTAIN IMPORTANT
INFORMATION. THE DEFINITIVE CONSENT STATEMENT WILL BE FILED BY SHELL OIL COMPANY
WITH THE SEC. INVESTORS AND SECURITY HOLDERS CAN OBTAIN A FREE COPY OF THE
CONSENT STATEMENT (WHEN AVAILABLE) AND OTHER RELEVANT DOCUMENTS ON THE SEC'S WEB
SITE.

IN ADDITION, THE IDENTITY OF PEOPLE WHO, UNDER SEC RULES, MAY BE CONSIDERED
"PARTICIPANTS IN THE SOLICITATION" OF BARRETT SHAREHOLDERS AND THEIR HOLDINGS OF
BARRETT COMMON STOCK ARE CONTAINED IN SHELL OIL COMPANY'S PRELIMINARY CONSENT
STATEMENT FILED WITH THE SEC UNDER REGULATION 14A.

THIS PRESS RELEASE CONTAINS FORWARD-LOOKING STATEMENTS THAT ARE BASED ON SHELL
OIL COMPANY'S CURRENT EXPECTATIONS, ESTIMATES AND PROJECTIONS. WORDS SUCH AS
"EXPECTS," "ANTICIPATES," "FORECASTS," "INTENDS," "PLANS," "BELIEVES,"
"PROJECTS," AND "ESTIMATES," AND VARIATIONS OF SUCH WORDS AND SIMILAR
EXPRESSIONS ARE INTENDED TO IDENTIFY SUCH FORWARD-LOOKING STATEMENTS.

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THESE STATEMENTS ARE NOT GUARANTEES OF FUTURE PERFORMANCE AND INVOLVE RISKS AND
UNCERTAINTIES AND ARE BASED ON A NUMBER OF ASSUMPTIONS THAT COULD ULTIMATELY
PROVE INACCURATE AND, THEREFORE, THERE CAN BE NO ASSURANCE THAT THEY WILL PROVE
TO BE ACCURATE.

ACTUAL RESULTS AND OUTCOMES MAY VARY MATERIALLY FROM WHAT IS EXPRESSED OR
FORECAST IN SUCH STATEMENTS. AMONG THE FACTORS THAT COULD CAUSE ACTUAL RESULTS
TO DIFFER MATERIALLY ARE CHANGES IN NATURAL GAS PRICES, CHANGES IN COMPETITIVE
OR ECONOMIC CONDITIONS AFFECTING SUPPLY AND DEMAND FOR GAS, PENDING OR FUTURE
LITIGATION, CHANGES IN CURRENT LAWS AND REGULATIONS, AND GENERAL DOMESTIC AND
INTERNATIONAL ECONOMIC AND POLITICAL CONDITIONS. SHELL OIL COMPANY UNDERTAKES NO
OBLIGATION TO UPDATE PUBLICLY ANY FORWARD-LOOKING STATEMENTS, WHETHER AS A
RESULT OF NEW INFORMATION, FUTURE EVENTS OR OTHERWISE.


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MEDIA CONTACTS:
Kitty Borah/Stacy Hutchinson     Shell Oil Media Relations        (713) 241-4544
David Sexton                     Shell Oil Investor Relations     (212) 218-3112
Web site information             www.shell-barrett.com/