The United States is putting pressure on the Japanese government to withdraw from a large Iranian oil program, the Financial Times reported here on Saturday.

The move is part of broader U.S. policy to persuade Iran to abandon its suspected nuclear weapons program and sign an agreement to allow United Nations inspectors access to all its nuclear facilities, the daily said, citing an unnamed U.S. official and sources close to the negotiations.

"A U.S. State Department official confirmed that the administration of President George W. Bush is pressing Japan not to send the 'wrong message' to Iran," it added.

The private but state-backed Japanese consortium includes Tomen Corp., Inpex Corp. and Japan Petroleum Exploration Co.

Representatives are now in Tehran and are expected to sign a contract within the next few days, as soon as they receive approval from Tokyo, it said.

The paper said Washington has been exerting constant pressure from various quarters.

U.S. Secretary of State Colin Powell raised the issue with Foreign Minister Yoriko Kawaguchi while U.S. National Security Adviser Condoleezza Rice has also contacted senior officials in Tokyo, it said.

The Japanese government is trying to resist the pressure, but signing the deal may be postponed until September, when further developments are expected at the International Atomic Energy Agency concerning Iran's nuclear programs, the paper added.

The oil project is to develop part of Azadegan, one of Iran's largest oil fields. In July 2001, Economy, Trade and Industry Minister Takeo Hiranuma agreed with Iranian President Mohammad Khatami on development of the region.

Japan hopes the oil project will secure an important source of energy supplies as it lost the rights to the Khafji oil field in Saudi Arabia two years ago.