By Nasser Karimi The Associated Press

TEHRAN, Iran – Iran notched up the brinksmanship over its disputed nuclear program yesterday, abruptly postponing talks with Moscow on a plan to enrich Tehran’s uranium on Russian territory to allay fears it is building an atomic weapon.

Diplomats in Europe said Iran had started small-scale enrichment of uranium, a process that can produce fuel for an atomic bomb.

“Uranium gas has been fed into three machines,” said a senior diplomat in Vienna, Austria, who spoke on condition of anonymity because he was not authorized to comment on the matter. Another diplomat confirmed that limited enrichment had begun at Iran’s Natanz site.

State-run Iranian television later reported that Alaeddin Boroujerdi, head of the national security and foreign relations committee in parliament, said the country had begun peaceful nuclear enrichment activities yesterday. Boroujerdi said inspectors from the Vienna-based International Atomic Energy Agency were present.

The talks with Russia had been slated for Thursday but were postponed indefinitely because of the “new situation,” said Iranian presidential spokesman Gholamhossein Elham. He was referring to the IAEA’s decision this month to report Iran to the U.N. Security Council because of uncertainty over its nuclear intentions.

Iran maintains its nuclear program is designed solely to generate electricity, but the United States and some U.S. allies claim the program is a cover for producing an atomic bomb.

Moscow had proposed that Iran ship its uranium to Russia, where it would be enriched to a level suitable for nuclear reactors. It would then be returned to Iran for use at the Russian-built Bushehr plant, which is due to begin operating this year.

The plan, backed by the United States and the European Union, was an attempt to avoid international objections to Iranian uranium enrichment by providing oversight so no weapons would be made. Iran had said the plan did not fulfill its requirements but was worth pursuing.