VIENNA, Nov 29: Iran escaped UN censure over its nuclear programme on Monday but Washington, which accuses it of seeking an atomic bomb, said it reserved the right to take the case to the Security Council on its own.

The International Atomic Energy Agency (IAEA) passed a resolution approving Iran's week-old suspension of sensitive nuclear activities as part of a deal between Tehran and the European Union.

Crucially, and in line with Iran's demands, the resolution described the freeze as a voluntary, confidence-building measure and not a legally binding commitment. Its passage meant that Tehran, which denies it wants the bomb, had achieved its immediate goal: to prevent the IAEA from referring it to the UN Security Council for possible economic sanctions.

"This resolution which was approved by the IAEA was a definite defeat for our enemies who wanted to pressure Iran by sending its case to the UN Security Council," President Mohammad Khatami was quoted by state radio as saying.

The United States alleges Iran is playing games with the international community and wants to see it referred to the Council. US envoy Jackie Sanders told the IAEA's board of governors that Washington reserved the right to go it alone.

"Quite apart from the question of how this board chooses to handle these matters, of course, the United States reserves all of its options with respect to Security Council consideration of the Iranian nuclear weapons programme," she said.

"Any member of the United Nations may bring to the attention of the Security Council any situation that might endanger the maintenance of international peace and security." Jackie Sanders also issued a stern warning to companies, including multinationals, against exporting weapons-related equipment to Iran. The United States "will impose economic burdens on them and brand them as proliferators", she said.

The statement reflected US frustration at Iran's repeated success in evading a referral to the Council, despite what IAEA chief Mohamed ElBaradei has called persistent unanswered questions and a "confidence deficit" over Tehran's activities.

Even if Washington took the issue to the Council it could expect strong resistance to punishing Iran with sanctions, including from permanent members Russia and China, which have veto powers.

A spokesman for US President George Bush said: "The implementation and verification of the agreement is critical." "Iran has failed to comply with its commitments many times over the course of the past year and a half...We will see, as time goes by, if they are now finally going to comply in full."

DIPLOMATIC POKER: The developments capped five days of diplomatic poker over the terms of a deal Iran struck with the EU this month to suspend all activities relating to enriching uranium. Enrichment generates fuel for use in nuclear power plants or, potentially, in weapons.