Iran has shrugged off US and EU warnings that it could be hauled before the UN Security Council and confirmed today it would resume some sensitive nuclear work soon.
"The decision to resume some activities has been taken and now we are discussing the timing for resuming. But this decision is imminent as well," Mohammad Saeedi, deputy head of Iran's Atomic Energy Organisation, told reporters.
Asked if Iran, which denies seeking nuclear arms, would restart machinery currently under UN seals immediately after the decision was taken, he said it would.
EU officials urged Iran today not to resume any nuclear activities that it agreed to freeze in a November agreement in Paris with Britain, France and Germany.
Since then, Iran and the EU trio have held several rounds of talks aimed at reaching a mutually acceptable long-term arrangement for Iran's nuclear programme. "The Paris agreement is based on one fundamental point - that the suspension remains in place," said a British government official in London.
"There are very clear consequences and Iran knows the implications. The follow-on implication is a referral to the UN Security Council," he added.
Asked if Iran was prepared to see its case sent to the Security Council, which could impose economic sanctions on Tehran, another senior Iranian official told reporters: "Iran is not prepared to see its rights violated."
Mr Saeedi said work would resume at the Isfahan Uranium Conversion Facility in central Iran. This plant converts raw uranium into a gas which can be used for uranium enrichment.
No uranium enrichment facilities are located at Isfahan itself. Iranian officials have said Tehran will not yet resume enrichment, a process which can produce bomb-grade material.