THE world ran out of patience with Iran yesterday after Tehran defied the United Nations by breaking the seals on an underground nuclear site and resuming enrichment work.

British officials said last night that Iran was likely to be referred to the UN Security Council for punitive sanctions by the end of the month.

The move comes after years of tortuous diplomacy aimed at curbing Iran’s nuclear ambitions and is a clear signal that the mediation efforts of Britain and other European countries are over.

The dramatic change of mood came after the latest act of defiance by President Ahmadinejad, Iran’s new hardline leader. On his orders Iranian technicians removed UN seals from equipment at the Natanz nuclear facility and two other sites, where enrichment work had been frozen for more than two years under an agreement with Britain, France and Germany.

Iran insists that mastering the enrichment of uranium is the key to completing the fuel cycle for its civilian nuclear reactor programme, which it insists it has every right to build. Critics around the world fear that the same technology will be diverted to produce highly enriched uranium, the core of an atomic warhead.

Mohamed ElBaradei, the director-general of the International Atomic Energy Agency (IAEA), said that he had “serious concerns” and accused Iran of “less than full and prompt transparency” in its dealings with the UN’s nuclear watchdog. The IAEA said that Iran was planning to begin small-scale enrichment work.

Jack Straw, the Foreign Secretary, who has devoted years of diplomatic effort to the mediation process, said that the decision was a matter of huge regret. He added: “We are profoundly concerned that Iran has decided to restart research and development activities related to uranium enrichment. There was no good reason why Iran should have taken this step if its intentions are truly peaceful and it wanted to resolve long-standing international concerns.”

The move has effectively killed the last hopes of Britain, France and Germany of achieving a negotiated solution with Iran. Their foreign ministers will meet in Berlin tomorrow and request an emergency meeting of the IAEA.

The organisation’s 35 governors will in turn vote to refer Iran to the UN Security Council, which has the power to impose sanctions.

President Chirac of France said that Iran would be committing a grave error if it ignored the concerns of the international community. Angela Merkel, the German Chancellor, said that Iran was sending worrying signals. The White House said that there was no other choice but to refer Iran to the Security Council. The European Union said that Iran was “continuously eroding international confidence” in its intentions. Even Russia, which is building Iran’s main nuclear power station, urged it to reimpose its moratorium on enrichment work at Natanz.

Mohammad Saeedi, the deputy head of the Iranian Atomic Energy Organisation, insisted that it was simply conducting research and development work for a civilian industry. But experts disagreed. “Once they begin enrichment they have crossed a red line,” said Mark Fitzpatrick, a former US diplomat and expert on nuclear proliferation at the International Institute for Strategic Studies.

He said that when the Iranians master enrichment technology, they will reach a “point of no return” in their ambition to build a nuclear weapon. At an IAEA meeting in September, Iran was found to be in breach of its commitments but given a final chance. Since then the international community has grown alarmed, in particular by Mr Ahmadinejad’s bellicose rhetoric, which has included repeated threats to destroy Israel.

The US is confident that it already has the simple majority of 18 votes it needs at the IAEA board of governors to win a referral to the UN. Once that happens a new diplomatic process will start among the 15 members of the Security Council on what action to take. A possible compromise is an offer by Russia to supply nuclear fuel to Iran. But Tehran has rejected the gesture.

COUNTDOWN

August 2002 Iranian opposition group identifies vast uranium enrichment facility at Natanz and a heavy-water plant at Arak

February 2003 IAEA inspects sites and accuses Iran of failing to comply with its obligations under the Nuclear Non-Proliferation Treaty

October 2003 Iran tells French, British and German foreign ministers that it will suspend enrichment work

June 2004 IAEA board says that Iran’s co-operation with the agency was incomplete. In reply, Iran says that it will resume production and testing of centrifuges

November 2004 Iran promises France, Britain and Germany that it will suspend nuclear fuel work

February 2005 President Khatami says that no Iranian government, present or future, will give up nuclear technology programmes. Iran signs a nuclear fuel supply deal with Russia, opposed by the United States, to start its first atomic power plant by 2006

August 2005 Iran breaks agreement with EU by resuming uranium conversion

September 2005 Iran held in breach by IAEA but is given one last chance to back down

January 2006 Iran removes UN seals at Natanz and resumes enrichment research

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