Iran on Thursday threatened to restart uranium enrichment if the European Union takes counter measures against a resumption of its uranium conversion activities.

"We would not be supposed to continue the suspension of the Natanz enrichment facilities if the Europeans called for an emergency meeting of the Board of Governors of the International Atomic Energy Agency (IAEA)," Hossein Moussavian, a top negotiator, told state television.

The nuclear plant in the central town of Natanz is used to pump uranium hexafluoride gas (UF6) into thousands of connected centrifuges to yield enriched uranium that could be used either in power stations or to make atomic bomb.

Iran said on Monday it would restart uranium conversion facility in Isfahan, which is used to turn uranium ore into UF6, because the EU ignored an August 1 deadline Iran set for it to deliver a promised comprehensive proposal on Iran's controversial nuclear program.

In reaction, the EU warned that a resumption of its nuclear work would mean the end of negotiations and that it would call for an emergency meeting of the Board of Governors of the IAEA to discuss on the referral of Iran's case to the UN Security Council, which could lead to sanctions on the Islamic Republic.

Moussavian said that Tehran expected to resume the uranium conversion activities as soon as the IAEA inspectors arrived in the central city Isfahan in about two days.

Iran's chief nuclear negotiator Hasan Rowhani said on Wednesday that Tehran hoped to resume the uranium conversion work by the beginning of next week. A week in Iran starts on Saturday.

"The IAEA has asked us to wait for a week so that they can put surveillance equipment in place," Rowhani said, adding that Iran would seek a possibly shortened wait.

Iran suspended all activities related to uranium enrichment in November 2004 in line with the Paris Agreement reached with the EU, but insisted that it's only a "temporary and voluntary move" and subject to future resumption.

The EU trio of Britain, France and Germany have promised to offer Iran a package of political and economic incentives in late July or early August to persuade Iran to permanently halt the uranium enrichment.

But Iran insists the EU recognize its right to enrich uranium as part of its nuclear program which Iran says is for fully peaceful purposes.

The United States has accused Iran of developing nuclear weapons under the veil of a civilian atomic fuel program, a charge rejected by Tehran as "politically motivated".

(Xinhua News Agency August 5, 2005)