Mahmoud Ahmadinejad promised to defend national interests and Islam in an inaugural speech that also reached out to millions of impoverished Iranians, whose votes swept him to a shock landslide election victory in June.

His success has raised the prospect of a clampdown on modernisers in Tehran and a curtailment of hard-won reforms, particularly among women. But yesterday’s inauguration focused on the impasse with the US and the European Union over Iran’s nuclear ambitions. While Iran maintains its right to nuclear energy under the nuclear non-proliferation treaty, America says that the nuclear programme is a veil for building a nuclear arsenal.

Ayatollah Ali Khamenei, Iran’s Supreme Leader, confirmed Mr Ahmadinejad’s presidency in a rousing speech peppered with anti-Western rhetoric. He denounced Western-style democracies, ordering the new Government not to give up “the rights of the nation”.

Mr Ahmadinejad did not directly refer to the nuclear crisis but called for an end to weapons of mass destruction. “Elements of global threat, including weapons of mass destruction, chemical and biological, must be eradicated,” he said.

Iran has threatened to resume its nuclear activities in defiance of the watchdog International Atomic Energy Agency (IAEA), and despite the latest plea by the EU.

This week Iran said that it planned imminently to resume uranium ore conversion, the first step in the cycle to produce fuel for nuclear reactors. There were mixed signals from Tehran yesterday, with officials suggesting that the process could begin next week, which may give the IAEA the time it says it needs to install monitoring equipment.

“We need until the middle of next week to get our surveillance equipment in place before any seals could be cut and nuclear activities started,” the IAEA said. The EU has warned Iran that any resumption of nuclear fuel activities will precipitate an end to two years of negotiations and will leave Iran facing sanctions by the UN Security Council.

Some analysts say that the timing of Iran’s threat to resume nuclear activities, just before Mr Ahmadinejad’s inauguration, is a canny strategic move preparing the way for Mr Ahmadinejad to step in and defuse the crisis, softening his image as a hardliner who wants to cut ties with the West. But Iranian officials have said that the timing was deliberate to protect Mr Ahmadinejad from charges of extremism.

Despite being a Robin Hood figure among working-class Iranians, revered for his modesty and honesty, he has been portrayed by Western media as a dangerous extremist with a shady past, which his aides say is part of a smear campaign to discredit Iran’s conservatives.

Washington has accused him of playing a key role in the 1979 US hostage crisis, despite denials from Mr Ahmadinejad and the original hostage-takers, who are mostly now radical reformers deeply opposed to the conservative camp. Austria is also investigating allegations that he was involved in the murder of Kurdish dissidents in Vienna in 1989, a charge his aides vehemently deny.

His win highlighted Iran’s stark class divides. While the other candidates were campaigning on social and political freedom, Mr Ahmadinejad, an outsider, tapped into Iran’s real problems — unemployment, poverty and corruption.

A staunch follower of the Supreme Leader, Mr Ahmadinejad wants a return to Islamic revolutionary values, and as mayor of Tehran he gained notoriety for pandering to his right-wing supporters with frequent crackdowns. He closed several cultural centres and turned them into prayer houses, and banned concerts and made city employees grow beards and wear long sleeves. He also famously banned advertising hoardings of David Beckham, the first Western celebrity to be used in advertising since the 1979 revolution, in a drive against “Westoxification”.

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