The U.N. atomic agency found traces of highly enriched uranium at an Iranian site linked to the country's defense ministry, diplomats said Friday, adding to concerns that Tehran was hiding activities aimed at making nuclear arms.
The diplomats, who demanded anonymity in exchange for revealing the confidential information, said the findings were preliminary and still had to be confirmed through other lab tests. But they said the density of enrichment appeared to be close to or above the level used to make nuclear warheads.
Still, they said, further analysis could show that the traces match others established to have come from abroad. The International Atomic Energy Agency determined earlier traces of weapons-grade uranium were imported on equipment from Pakistan that Iran bought on the black market during nearly two decades of clandestine activity discovered just over three years ago.
Uranium enriched to between 3.5 percent and 5 percent is used to make fuel for reactors to generate electricity. It becomes suitable for use in nuclear weapons when enriched to more than 90 percent.
Iran's refusal to give up enrichment ambitions has led to involvement by the U.N. Security Council, which has the power to impose sanctions but remains split on how firmly to pressure Tehran.
Key U.N. Security Council members agreed Tuesday to postpone a resolution that would have delivered an ultimatum to Tehran, giving Iran another two weeks to re-evaluate its insistence on developing its uranium enrichment capabilities.
Iran's hard-line president said Friday that his country was not afraid of possible U.S. military action over its enrichment program, but added that he thought any such strikes were very unlikely. Washington has said it favors a diplomatic end to the dispute, but it hasn't ruled out military force.
President Mahmoud Ahmadinejad also told a local TV station that Iran would cooperate with the Security Council if it makes a decision on the escalating standoff as long as the world body acts "in line with international rules."
The Islamic republic denies accusations it wants to make nuclear arms and says it is only interested in uranium to generate power.
To argue that it never enriched uranium domestically to weapons grade, it cites the IAEA's tentative conclusion last year that weapons-grade traces collected from other sites within the country with no suspected ties to that military came in on equipment from Pakistan.
The origin of the samples now under perusal created some concern in that regard.
One of the diplomats told The Associated Press that the samples came from equipment that can be used in uranium-enriching centrifuges at a former research center at Lavizan-Shian. The center is believed to have been the repository of equipment bought by the Iranian military that could be used in a nuclear weapons program.
The United States alleges Iran had conducted high-explosive tests that could have a bearing on developing nuclear weapons at the site.
The State Department said in 2004 that Lavizan's buildings had been dismantled and topsoil had been removed in attempts to hide nuclear weapons-related experiments. The agency subsequently confirmed that the site had been razed.
In an April 28 report to the U.N. Security Council and the IAEA's 35-nation board of governors, agency head Mohamed ElBaradei said the agency took samples from some of the equipment of the former Physics Research Center at Lavizan-Shian. The diplomat said the evaluation of those samples revealed the traces in question.
Ahmadinejad's remarks on possible U.S. military action were made in Jakarta during a discussion with Indonesian Islamic leaders.
Asked whether his country was prepared to face an attack by the United States, he said "that is very unlikely because they know the Islamic Republic of Iran is a strong country."
"They are trying to frighten our country by waging a propaganda campaign using strong words. The people of Iran and the country are not afraid of them," he said to applause from the audience.
The Chinese and Russians have balked at British, French and U.S. efforts to put the resolution under Chapter 7 of the U.N. Charter. Such a move would declare Iran a threat to international peace and security and set the stage for further measures if Tehran refuses to suspend its uranium enrichment operations. Those measures could range from breaking diplomatic relations to economic sanctions and military action.