US flexes muscles as it sends aircraft carriers to Persian Gulf

The United States sent Iran a message of intent yesterday by despatching two aircraft carriers to the Gulf region just days before the resumption of negotiations over Tehran's nuclear programme.

A file photo of the aircraft carrier USS Enterprise

The US navy announced the arrival of the USS Abraham Lincoln in the north Arabian Sea and the USS Enterprise, the world's longest naval vessel, in the Gulf of Aden.

A senior official in President Mahmoud Ahmadinejad's government threatened in January unspecified action if American aircraft carriers returned to the Persian Gulf, saying: "We are not in the habit of warning more than once".

Although neither ship has entered the Gulf itself, the deployment will be seen as an unmistakable challenge in Tehran ahead of the beginning of negotiations on Saturday, which President Barack Obama has described as Iran's "last chance" to resolve the nuclear impasse through diplomacy.

In recent weeks Iran has been forced to temper its bellicose rhetoric after American and European Union sanctions against the country's central bank and energy sector began to have serious consequences for its already faltering economy.

In an apparent gesture of reconciliation, Iran offered to resume talks with the international community over the future of its nuclear programme, which it continues to insist is purely for peaceful purposes.

Despite strong Israeli misgivings and deep suspicions in the West, Iran's negotiating partners accepted the offer but have outlined a series of initial steps they expect Tehran to take to prove its sincerity.

These include a demand for the closure of Iran's best protected nuclear facility at Fordow and an immediate halt to the refinement of uranium to a concentration of 20 per cent, a level considered a short step away from weapons grade. All stocks of nuclear fuel enriched to 20 per cent must also be shipped abroad, Western diplomats said.

Iran reacted angrily to the demands yesterday, accusing world powers of an act of bad faith by announcing conditions before the talks, which are to be held in Istanbul, had even begun.

"Setting conditions before the meeting means drawing conclusions, which is completely meaningless and none of the parties will accept conditions set before the talks," Ali Akbar Salehi, Iran's foreign minister, said.

But in a sign that Iran is willing to give at least the impression of compromise, the country's nuclear chief, Fereydoun Abbasi, said that Tehran was willing to contemplate halting the enrichment of uranium to 20 per cent – but only once it had stockpiled nuclear fuel at that level.

"The job is being carried out based on need," he said. "When the need is met, we will decrease production and it is even possible to completely revert to only 3.5 per cent (levels)."

Western powers are likely to reject the offer, however. Iran has already produced 240lb of uranium enriched to 20 per cent – just under the amount needed to produce one nuclear bomb if refined further – and has announced that it needs to treble that amount.