Ex-aide says Rice misled Congress on Iran

Leverett and others have represented the proposal as a missed opportunity that could have defused tensions with Iran which have grown to the point that the U.S. administration has been forced to deny it plans military action against Tehran.

Leverett said Rice should apologize for calling his competence into question.

He said he had left the National Security Council, which advises the president on security issues, in March 2003 before the Iranian proposal was received. He returned to the CIA where he previously worked and soon after left government. Hence, he was not in a position to make this case directly to Rice, he said.

Leverett said Powell, in a conversation about the Iranian proposal, told him he "couldn't sell it at the White House." This was evidence it had been discussed there, he said.

The proposal was transmitted in May 2003 by the Swiss ambassador in Tehran, Tim Guldimann, who represented U.S. interests there. Washington has not had diplomatic relations with Iran since two years after the 1979 Islamic revolution.

According to a copy of the proposal posted on The Washington Post Web site and cited by Leverett, it contains considerable detail about approaching issues of central interest to the United States and Iran.

This included an end to Iran's support for anti-Israel militants and acceptance of Israel's right to exist.

It carried a cover letter from Guldimann, who said the proposal was approved by Iran's supreme religious leader, Ayatollah Ali Khameini, and then-President Mohammed Khatami.