BRITAIN warned Iran yesterday to back off from its “unnecessary and damaging threat” to resume part of its nuclear programme.

The Foreign and Commonwealth Office said that if Iran were to resume its uranium conversion programme, talks between Tehran and the European Union that have been going on for two years would probably be halted.

The next step may see Britain referring Iran to the United Nations Security Council, followed by sanctions and a stand-off between the United States and Iran.

In its statement the Foreign Office said that if Iran does not back down it will consult the board of the International Atomic Energy Agency (IAEA) before acting. The Iranians suspended their nuclear programme last November in accordance with IAEA resolutions and the “Paris Agreement” with the EU3 — Britain, France and Germany.

The EU countries will offer economic incentives in return for a suspension of uranium enrichment, nuclear fuel reprocessing and related activities that Washington says are part of efforts to build a nuclear bomb.

But in a last-minute twist, typical of the negotiations between Iran and the EU, Tehran said that the EU agreed to August 1 as a deadline for presenting the proposals.

The statement came only a few days before the inauguration of Iran’s new ultra-conservative president-elect, Mahmoud Ahmadinejad, who has said that he will send a tough message to Europe about Iran’s nuclear ambitions.

Analysts are uncertain about the extent to which he will influence nuclear policy because he may not have much power in that area. That right is bestowed upon Ayatollah Khamenei, the supreme leader, and the supreme national security council, of which the President is a member but not the deciding influence.

The EU3 denied that such a deadline was agreed and said that it promised proposals by late July or early August.

The Foreign Office said: “The Foreign Ministers (of Britain, Germany and France) and the EU high representative have just written to Iran’s chief negotiator on nuclear activities — confirming that full and detailed proposals would be given to Iran in a week’s time.”

Iran claims that it will resume only a gas conversion process, which it says is not part of the suspension. The nuclear plant in the central city of Esfahan takes uranium ore from Iran’s deserts and turns it into hexafluoride gas, which is used to enrich uranium.

Ali Aghamohammadi, a spokesman for the Supreme National Security Council, said: “The only activity we will resume is to lift part of the uranium conversion facility at Esfahan and it will be only limited activities.”

A Foreign Office source said that Iran made the same threat ten weeks ago.

The IAEA said last night it would take at least three days to convene an emergency meeting if the crisis escalated.

RAW MATERIALS

The International Atomic Energy Agency is concerned that Iran is building a heavy water research reactor in Arak, south of Tehran. It could produce 8 to 10kg of plutonium a year, enough to make at least one nuclear bomb

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