Iran has resumed some uranium enrichment work, a first step towards making fuel for atomic reactors or bombs, in defiance of a vote reporting Teheran to the UN Security Council, diplomatic sources said Monday.

Iran had said it would restart enrichment, shelved for two years under Western pressure, by early March but gave no date.

An official in the Iranian capital would only say that "Iran was supposed to resume uranium enrichment on Sunday or Monday," without confirming whether the process had started.

If confirmed, Iran's bold moves signaled it would try to overcome any action to rein in its nuclear program after the February 4 decision by the International Atomic Energy Agency (IAEA) to involve the Security Council, which could consider sanctions.

Iran retaliated for the IAEA vote by halting short-notice inspections by agency personnel, a key tool in investigations to assess whether Iran's nuclear program was wholly peaceful or not, and vowing to resume uranium enrichment.

"We heard from reliable sources that enrichment work resumed last night at Natanz," said one Vienna-based diplomat.

He was referring to a pilot fuel-purification plant where Iran began renovating mothballed equipment last month, prompting the European Union to sponsor a resolution at the IAEA to notify the Security Council after diplomacy with Teheran broke down.

Greenpeace nuclear analyst William Peden said Iranian efforts to purify uranium at this stage would involve only testing of a few centrifuges, a long way away from the hundreds needed to produce fuel for atomic warheads.

Diplomats and nuclear experts have estimated Iran would need between two and more than 10 years to perfect technology needed to create a nuclear arsenal, if it indeed wants one.

Talks with Russia postponed

In Teheran earlier, government spokesman Gholamhossein Elham said this week's talks with Russia to discuss proposals to process nuclear fuel for Iranian reactors on Russian soil had been postponed.

The proposal was put forward by Moscow to ease international concerns that enrichment via a joint venture inside Iran would not prevent possible diversions into a shadowy weapons project.

"Talks with Russia have not been cancelled, but the date should be discussed," Elham told a weekly news conference.

He said the proposal was acceptable only if it was in addition to enrichment facilities in Iran. "The government insists on enriching uranium on Iran's soil and the proposal should be adjusted based on the new circumstances."

Russia's RIA news agency quoted Foreign Ministry spokesman Alexei Sazonov as saying: "We have not received from our Iranian partners any notification of talks planned for February 16 being postponed for some reason."

He said it was "premature" to talk about their cancellation or postponement.

Earlier, Russian Deputy Foreign Minister Sergei Kislyak was quoted as saying: "Our proposal to meet on February 16 still stands."

(China Daily February 14, 2006)