WASHINGTON – President Bush yesterday expressed skepticism at Iran’s recent pronouncement that they have suspended the enrichment of uranium as the U.N. nuclear watchdog began meetings to discuss the specter of Iran obtaining a nuclear weapon.

Echoing President Reagan’s famous quip regarding Soviet accession to arms-control agreements, Mr. Bush, speaking to reporters yesterday in Colombia, said, “I think the definition of truth is the willingness for the Iranian regime to allow for verification. You know, they have said some things in the past, and it’s very important for them to verify and earn the trust of those of us who are worried about them developing a nuclear weapon.”

At a meeting in Vienna on Thursday of the member states of the International Atomic Energy Agency, the director general of the organization, Mohamed El Baradei, is expected to give his verdict on whether Iran has kept its most recent pledge to suspend enrichment. Iran has broken prior promises of suspension.

Meanwhile, British, French, and German diplomats are nearly finished with the final agreement announced earlier this month that would spare Iran yet again from potential censure and sanction in the U.N. Security Council for its prior violations of the nuclear nonproliferation treaty.

As recently as October, the White House was pushing for a vote from the IAEA board of governors to refer Iranian enrichment activities to the Security Council.

Earlier this month, however, the governments of France, Germany, and Britain announced that they had a forged a deal with Tehran that essentially promised the eventual delivery of reactors and parts for more promises from the Iranians to abandon any nuclear weapons programs. The European deal scuttles any referral to the United Nations for now.

But diplomatic sources and one administration official told The New York Sun that Americans are trying to include language in the European-Iranian agreement that would trigger referral to the Security Council if there is any evidence of Iranian violations of this agreement. Also, the American delegation in Vienna is pushing for the agreement to have tougher verification procedures.

A State Department deputy spokesman, Adam Ereli, yesterday would not comment on the European-Iranian deal, but he did say America had been consulting the Europeans on their talks.

“We consulted with the E.U.-3 on this deal,” he said. “But we leave it to them and the Iranians to comment on its provisions and on next steps. Obviously, this would be an issue under discussion at the Board of Governors meeting and we’ll, you know, we’ll be making our views clear.”

Despite promises Iranian diplomats made in 2003 to suspend enrichment while the IAEA inspected previously undisclosed centrifuges and laboratories, the regime resumed enrichment over the summer. Mr. ElBaradei told the Agence France-Press yesterday that Iran has produced 2 tons of uranium hexafluoride, which the IAEA director general said would provide 15% of what was needed to make a nuclear bomb.

As things move quickly on the negotiations with Iran, European diplomats have also pressed Washington since the president’s re-election for a clear statement of overall American policy toward Iran. As national security adviser, the president’s nominee for secretary of state, Condoleezza Rice, vetoed a Pentagon draft national security policy directive that would have made America’s official stance toward Iran one of regime change. Legislation introduced this year by Senator Santorum, a Republican of Pennsylvania, would also make this official American policy. That bill is stalled in the Senate Foreign Relations Committee, but Mr. Santorum’s spokeswoman said he plans to reintroduce the legislation when Congress returns in January.

Senator McCain, a Republican from Arizona, on Sunday hinted that America might eventually have to take military action against Iran if the ruling mullahs there do not stand down from the nuclear threats in the coming months.

“The next step obviously is to try to get the Security Council to act in some meaningful fashion,” he told Tim Russert on NBC’s “Meet the Press.” “But, you know, Tim, this is a harsh comment, but at the end of the day, it’s the United States of America that may have to act if we act, but I hope that we can dissuade them through other means.”

The deputy director for the Washington Institute for Near East Policy, Patrick Clawson, said in an interview yesterday that one of the major issues the Europeans will have to address in their agreement is Iranian development of a nuclear warhead.

“Iran could be suspending its enrichment activities but continuing its development of a nuclear warhead and delivery system,” he said.

Secretary of State Powell last week made headlines when he spoke about intelligence that suggested the Iranian development of such a warhead.

Mr. Clawson also said that the IAEA was ill-equipped to deal with Iran’s recent violations. “The history of the IAEA is to look for cooperation and forgive past lack of compliance for promises of cooperation,” he said. “After 18 years of not complying and over the last two years changing stories completely, the United States should not be asking for cooperation. We should not allow Iran to have the dangerous technologies it would have a right to under the nuclear nonproliferation treaty.”

Iran’s foreign minister, Kamal Kharrazi, is in Sharm el-Sheikh today for a meeting of Iraq and its neighbors on stability in the country and the upcoming elections. Mr. Powell will also attend the summit but has said he will not meet separately with his Iranian counterpart.

In a related matter, the State Department issued a new travel warning for Americans planning to visit Iran. It said, “Tensions generated by the current situation in Iraq have increased the potential threat to U.S. citizens and interests abroad posed by those who oppose U.S. policy. Some elements of the Iranian government and population remain hostile to the U.S. American citizens may be subject to the possibility of harassment or kidnapping.”