IRAN’S supreme leader yesterday threatened to disrupt the West’s oil supplies from the Gulf if Iran was attacked, and insisted that the country would not give up its nuclear ambitions.

Addressing a rally in southern Tehran, Ayatollah Ali Khamenei appeared to toughen Iran’s position before a visit this week by Javier Solana, the EU’s foreign policy chief. Mr Solana will present the regime with a new package of incentives from the international community that would allow a civilian nuclear power industry but stop controversial uranium enrichment.

“If you make any mistake, definitely shipment of energy from this region will be seriously jeopardised. You have to know this,” said Ayatollah Khamenei, hinting that Iran might attack oil shipments through the Strait of Hormuz if it was targeted. “You will never be able to protect energy supply in this region.”

Condoleezza Rice, the US Secretary of State, dismissed the threat and promised a tough international response if Tehran refused to suspend its nuclear activities. Appearing on US Sunday chat shows, she gave Iran “weeks” to respond to a Western ultimatum that it halt its uranium enrichment programme and return to negotiations, or face UN action.

“I think something like 80 per cent of Iran’s budget comes from oil revenue, and so obviously it would be a very serious problem for Iran if oil were disrupted on the market,” she said.

Late last week the US, its European allies, Russia and China agreed the package that Mr Solana will present to the Iranian regime. The details have not been published, but diplomats said that the US had offered to lift some trade sanctions against Iran. Dr Rice said that it also included a threat of stern measures if Iran refused to cooperate, despite the reluctance of Moscow and Beijing to back sanctions. “We are absolutely satisfied with the commitments of our allies to a robust path in the Security Council should this not work,” she said.

Ayatollah Khamenei’s remarks signalled a hardening of attitudes in Iran only a day after President Ahmadinejad said that Tehran would be prepared to consider the offer from the international community, which includes direct talks with the US for the first time in more than a quarter of a century.

Times Recommends

• Should Knox’s trial even have reached the courtroom?
• 'Was it real?' The US bailout nightmare
• Iranian opposition plays the long game