TEHRAN, Sept. 20 - Iran's chief nuclear negotiator warned Tuesday that the country would resume enriching uranium and restrict United Nations inspectors from critical information if the United States and its allies used the "language of threat" by referring Iran to the Security Council.
The negotiator's threat, which appeared to be backed by Iran's supreme religious leader, Ayatollah Ali Khamenei, came as a confidential draft resolution circulating at the governing board of the International Atomic Energy Agency included a call for the Security Council to take up "Iran's many failures and breaches of its obligations." But the draft makes no specific reference to sanctions, which are still opposed by China and Russia, both of which hold veto power in the Council. A copy of the resolution was provided to The New York Times by an official involved in the behind-the-scenes diplomacy over how the board should deal with Iran at its meeting this week.
The comments by the Iranian negotiator, Ali Larijani, in a news conference here on Tuesday were the first time that Iran had explicitly threatened to cut off inspections and resume enriching uranium - which it insists will be used for civilian reactor fuel, not nuclear weapons - if the atomic agency's board acts.
Mr. Larijani, who is also secretary of Iran's Supreme National Security Council, is newly appointed to his post as negotiator on nuclear issues, and the news conference was his first since President Mahmoud Ahmadinejad took office last month. In a fiery speech on Saturday in front of the United Nations General Assembly, Mr. Ahmadinejad criticized the United States and its allies and vowed to press ahead with Iran's nuclear program, noting that it had a right under the Nuclear Nonproliferation Treaty to produce nuclear fuel. The Bush administration maintains that Iran gave up that right by hiding, for more than 17 years, a range of nuclear activities that United Nations inspectors only discovered with the help of intelligence agencies and Iranian dissidents.
Last week in New York, the senior State Department official on nonproliferation, Robert Joseph, briefed seven nations on the I.A.E.A.'s board about evidence that the United States has collected that it says shows that Iran's missiles could be used to launch nuclear warheads, according to a senior administration official, who insisted on anonymity because he was discussing intelligence matters. Among the countries that received the briefing were Ghana, Argentina and India. But American officials insist that the briefings were classified, and they have declined to make public the details of their suspicions.
Iran's threat came only 24 hours after the United States and North Korea reached an agreement in principle for the North to give up its nuclear weapons and all other nuclear facilities. But that accord seemed in jeopardy within hours of its signing, and it is being closely watched by Iranian officials.
Mr. Larijani said the world should learn a lesson from the case of North Korea, which American intelligence officials believe has produced fuel enough for six or eight weapons. He said the Bush administration's efforts to isolate the North had failed. "What was the result of such tough policies?" he asked. "After two years they ended up accepting its program, so you should accept ours right now," he said.
American officials say they have never accepted the North's weapons program; Mr. Larijani may have been referring to President Bush's decision to discuss allowing the North to keep a light-water reactor.
What was striking to several American experts interviewed Tuesday was that Iran's threats seemed to be drawn from the strategy that North Korea pursued three years ago, when it was confronted by American allegations that it had started a second, clandestine nuclear program to evade a freeze on nuclear activities that it had negotiated with the Clinton administration in 1994. At the end of 2002, the North threw out international inspectors and withdrew from the nonproliferation treaty, though Iran has not threatened to go that far.
"The North Koreans were using the Iranian example as well, saying that if they are allowed to keep a reactor, why can't we?" said Jack Pritchard, a former State Department official who dealt with the North and left the department in disagreement with the Bush administration's strategy. "Having these negotiations with North Korea and Iran take place simultaneously means that both countries use the other's tactics, and I'm sure the administration wished that was not happening."
Ayatollah Khamenei, Iran's religious leader, said in a statement read on state television on Tuesday, "The great Iranian nation today, stronger than before and with a determined will to reach its aims and goals, stands solidly and will not surrender to any sort of pressure and threat."
Mr. Larijani emphasized that the ability to enrich uranium was Iran's right under the nonproliferation treaty. The United States and Iran's three European negotiating partners, Germany, Britain and France, have insisted that Iran not be allowed to do so, however, because the enrichment process can also be used to produce weapons.
"If they want to use the language of force against Iran, Iran will definitely review its relations with the nuclear agency and its commitments to N.P.T.," he said. "If they want to use the language of threat, or send Iran's case to the Security Council, Iran will think twice about implementing the Additional Protocol and will resume uranium enrichment."
The Additional Protocol is an addendum to the treaty that allows the I.A.E.A. to conduct intrusive inspections of sites that a country has not declared are part of its nuclear program. Iran adopted it in 2003 and started carrying out its procedures, but the Parliament has not ratified it.
Mr. Larijani also rejected calls for a deadline for the country to stop work at the fuel-conversion facility at Isfahan, saying that setting a deadline was equal to sending Iran's case to the Security Council. "Pressuring a country like this is resisting a country's national pride," he said, referring to the country's achievements in nuclear science and compared it with nationalization of oil in the 1950's. "Two years of negotiations and hiding intentions has made Iran frustrated and it seems that the three European countries have humiliated Iranian people," he said.
To reach a compromise, the three European countries have insisted that Iran freeze its enrichment of uranium fuel, but have promised to provide the country with fuel for its plants. Control would remain in European hands.
Mr. Larijani said Tuesday that that was not acceptable. "There is no international guarantee that governments would provide us with nuclear fuel," he said. "We cannot lay the fate of this nation in the hands of other governments."
Both President Bush and Secretary of State Condoleezza Rice have said in recent days that they think a referral of Iran to the United Nations Security Council for possible sanctions is nearly certain but its timing is not.
"I am quite certain that at some point in time Iran is going to be referred to the Security Council, particularly if Iran continues to demonstrate that it is not prepared to give the international community assurances that is not going to try to build nuclear weapons under cover of civil power," Ms. Rice said.
