Ultramar Diamond Shamrock Corp. and Ceres Hellenic Shipping Enterprises Ltd. Announce Strategic Agreement.

Business Editors and Energy Writers

SAN ANTONIO--(BUSINESS WIRE)--April 17, 2000

Ultramar Diamond Shamrock Corp. (NYSE:UDS) and Ceres Hellenic Shipping Enterprises Ltd. today announced a 10-year agreement for a fifth Suezmax tanker to be used in the company's crude transportation program. The vessel, which will be owned by Ceres and built by Hyundai Heavy Industries, Ltd., is scheduled for delivery in late 2001.

UDS earlier announced a seven-year agreement with Sonatrach, the Algerian national oil company, for an additional 35,000 barrels per day of light, low-sulfur crude oil for delivery to the company's Quebec refinery located northeast of Montreal on the Saint Lawrence River.

"This agreement is an important part of our strategy to grow earnings and return through integrated operations," said Jean Gaulin, UDS Chairman and CEO. "Our agreement with Sonatrach secures an additional supply of quality crude oil and our agreement with Ceres secures the means of safely and efficiently transporting the additional volume to our facilities."

The $54 million, 160,000 metric-ton vessel will be built to 40-year trading standards. Special grade steel, capable of withstanding the very low temperatures of the North Atlantic, will be used in the construction of its ice-strengthened, double-walled hull. An increased beam and shallower draft will allow for maximum cargo intake and fully laden deliveries into the shallow marine terminals of the Saint Lawrence River. The vessel's lower draft will also provide UDS the flexibility of delivering cargoes to Corpus Christi, Texas, for refining in its Three Rivers facility.

The environmentally advanced tanker is also designed to eliminate the potential for contamination of sea water in emergency ballast situations. In heavy weather, sea water is often pumped into unused cargo tanks to add ballast and stability. The new vessel will be built with segregated ballast tanks that will prevent sea water from coming into contact with remnant crude oil during these emergency ballast operations. The segregated ballast capacity will be over 50% of the vessel's total deadweight.

Ultramar has focused almost exclusively on very modern, ice-strengthened double-hulled tankers for its crude oil program. The "Cap Georges," "Cap Laurent," "Cap Jean" and "Cap Romuald," which were all built in 1998, presently serve as the core lifting capacity for the company's Quebec deliveries from the North Sea, Mediterranean and West Africa.

UDS and Ceres have been strategic partners in time-charters and spot voyages to Quebec since the late 1980s. This technologically advanced and environmentally sensitive tanker represents a strategically important addition to the Ceres managed fleet as well as to Ultramar Diamond Shamrock's long-term crude transportation program.

Ultramar Diamond Shamrock Corp. (NYSE:UDS), with about $14.0 billion in annual revenues and more than 21,000 employees, is one of the largest independent refining and marketing companies in North America. The company operates six refineries in the United States and Canada with a total throughput capacity of 649,000 barrels per day and has over 5,000 branded retail gasoline/convenience merchandise stores, the majority of which are branded Diamond Shamrock, Ultramar, Beacon or Total. The corporation also has growing petrochemicals and home heating oil businesses. Please visit our Web site at http://www.udscorp.com for more information including annual reports, press releases, SEC forms 10-K and 10-Q, and audio archives of recent conference calls.