Controversy over a possible missed US opportunity for rapprochement with Iran grew yesterday as former aide accused Secretary of State Condoleezza Rice of misleading Congress on the issue.
Flynt Leverett, who worked on the National Security Council when it was headed by Ms Rice, said a proposal vetted by Tehran's most senior leaders was sent to the United States in May 2003 and was akin to the 1972 US opening to China.
Speaking at a conference on Capitol Hill, Leverett said he was confident it was seen by Ms Rice and then-secretary of state Colin Powell but that "the administration rejected the overture".
Ms Rice's spokesman denied she misled Congress, however, and reiterated that she did not see the proposal.
Separately, Undersecretary of State Nicholas Burns warned Iran it risked further UN and other sanctions if it did not halt uranium enrichment as the UN Security Council demanded.
He stressed there was still time for diplomacy before Iran reached a critical point in its nuclear capability and said conflict with Iran was not inevitable.
Washington remains patient and committed to negotiations with Tehran, and its carrot-and-stick approach with other major powers is influencing Iran's internal debate, Mr Burns told the Brookings Institution think tank.