Venezuela has agreed to sell its minority share in the Lyondell-Citgo refinery in Texas to Lyondell Chemical Co. for about US$1.3 billion, Venezuela's oil minister said Tuesday.

Oil Minister Rafael Ramirez said the sale of the 41-percent stake in the refinery was finalized after two years of study and negotiation.

"It isn't a surprise for anyone," Ramirez said. "Our teams have been working on this sale for two years."

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Houston-based Citgo Petroleum Corp., a wholly owned subsidiary of Venezuela's state oil company, and Lyondell Chemical Co. had announced in April plans to sell their jointly owned, 268,000 barrel-a-day refinery in Houston.

President Hugo Chavez says the Citgo refineries have been a bad deal for his oil-rich South American nation because they buy Venezuelan oil at a discount and pay taxes in the United States.

Chavez has warned he could cut off oil exports to the U.S. if it were to attack his country, but Washington has dismissed that suggestion as ridiculous. The United States remains the top buyer of oil from Venezuela, and Chavez says he intended to continue selling to the U.S. market while also increasing sales to other countries like China.

Venezuela, the world's No. 5 oil exporter, remains largely dependent on its U.S. refineries because its heavy crude can only be processed in a limited number of refineries elsewhere.

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