But the agency was stonewalled by Iran's refusal to give more information on other key issues ¡ª details of its centrifuge programs that are used to enrich uranium, information on drawings that show how to form fissile uranium into warheads, and apparent links between Iran's military establishment and what it says is a civilian nuclear program.

The Security council is likely to consider punitive measures against the Islamic republic. While Russia and China have been reluctant to endorse sanctions, the council's three other veto-wielding members say a strong response is in order.

The report formally served notice that Tehran had shrugged off a 30-day deadline to meet council demands. As such, it opened the way for further council steps, including the potential threat of sanctions and military action if Iran continues to defy the international community.

Secretary of State Condoleezza Rice won broad support from NATO allies for a tough diplomatic line on Iran.

However, NATO foreign ministers meeting in Sofia, Bulgaria, did not offer any specific threat of sanctions against Iran. While Russia and China have been reluctant to endorse sanctions, the council's three other veto-wielding members say a strong response is in order.

"On Iran, there was unanimity," Spanish Foreign Minister Miguel Angel Moratinos told reporters. "Although the clear message to the Iranian authorities is one of firmness, we have to continue with the diplomatic path."

Rice said it was time for the Security Council to act if the world body wished to remain credible.

"The Security Council is the primary and most important institution for the maintenance of peace and stability and security and it cannot have its word and its will simply ignored by a member state," Rice said.

Iran's UN ambassador, Javad Zarif, said Thursday that Tehran will refuse to comply even if the council request is turned into a demand through a resolution because its activities are legal and peaceful. Enrichment can be used to generate fuel or make the fissile core of nuclear weapons.

"If the Security Council decides to take decisions that are not within its competence, then Iran does not feel obliged to obey," he said in New York.

As late as Thursday, Russian President Vladimir Putin questioned the primacy of the council, insisting the UN nuclear watchdog should continue to play a central role in the dispute. "It mustn't shrug this role from its shoulders and pass it on to the UN Security Council," Putin said.

But a top French diplomat laid out a starkly contrasting position that also reflects US and British views: The Security Council should not only have the main say in dealing with Iran but also should start considering how to increase the pressure. But, the diplomat said, a UN resolution enforceable by military action would not automatically mean resorting to such action.

The Security Council statement a month ago gave Iran until Friday to suspend all activities linked to enrichment because it can be used to make the highly enriched uranium used in the core of nuclear warheads.

Instead of complying, Iran ¡ª which says it seeks the technology only to generate electric power ¡ª has upped the ante in recent weeks, announcing it had for the first time successfully enriched uranium and was doing research on advanced centrifuges that would let it produce more of the material in less time.

Western concern has grown in the more than three years since when Iran was found to be working on large-scale plans to enrich uranium.

While the IAEA has found no "smoking gun" proving Iran wants nuclear arms, a series of reports have revealed worrying clandestine activities ¡ª like plutonium processing ¡ª and documents, including drawings of how to mold weapons-grade uranium metal into the shape of a warhead.