THE president of Iran, Mah-moud Ahmadinejad, has taken to regaling his inner circle with a startling anecdote from his travels around the country to bolster domestic support for a nuclear programme that has generated vociferous international opposition.

Flying back to Tehran one day from a western province, he realised that he would not reach the capital in time for a scheduled prayer and ordered his helicopter pilot to land.

As Ahmadinejad tells it, he had just laid out his prayer mat on the flat, fertile terrain of rural Zanjan when three shepherds appeared and began to chant. “Nuclear power is our inalienable right,” they cried in faithful unison.

The story, recounted last week by one of the president’s advisers, is viewed by aides as an illustration of popular backing for uranium enrichment despite the United Nations sanctions it has provoked at a time of growing economic hardship in Iran.

To foreign diplomats, however, it is another sign that Ahmadinejad - who once claimed to have been surrounded by an aura while speaking to the UN and who has called for Israel to be wiped off the map - is becoming, in the words of one western official, “increasingly divorced from reality”.

Diplomats find it hard to judge who really speaks for Iran today. Ayatollah Khamenei, the supreme leader, has the ultimate power but says little in public, while his president’s rhetoric is often at variance with more businesslike statements from other senior officials in parallel power structures.

Ahmadinejad, head of the conservative hardliners whose scant knowledge of the outside world is a source of pride, has found himself pitted against a group of conservative pragmatists such as Ali Larijani, secretary-general of the Supreme National Security Council and Iran’s chief nuclear negotiator, who represents a more sophisticated approach to international relations.

At an Army Day parade in Tehran last week, Ahmadinejad spoke belligerently about western attempts to halt the production of enriched uranium for fear that it will be used for nuclear weapons rather than nuclear energy as Iran claims.

“The army stands against any aggressor and will cut off their hand,” he declared as he reviewed a procession of tanks, gaily painted missiles on flatbed lorries and even two mini-submarines trundling by in the spring sunshine.

In contrast, Larijani’s more moderate tone was in evidence in recent comments that Iran was interested in dialogue and in improving relations with Washington.

The saga of the 15 British sailors and marines detained in the Shatt al-Arab waterway last month highlighted a fault line of growing significance in Iranian politics. The Revolutionary Guards, one of the pillars of support for Ahmadinejad, imprisoned them and made talks about their release all but impossible. They are said to have shown no sense of urgency and no understanding of the pressures faced by the British government.

In the end Larijani - who believes that, to survive, the regime has to engage with the West - stepped in and defused the crisis. He recommended to the supreme leader that the servicemen be freed and then had a long talk about it with Sir Nigel Sheinwald, Tony Blair’s foreign policy adviser.

Ahmadinejad and Larijani ran against each other for the presidency in 2005 and represent factions vying for power in parliamentary elections next year and presidential elections in 2009.

Many Iranians believe that Ahmadinejad’s international posturing on the nuclear issue and UN sanctions may have backfired at home. A steep drop in support since he was voted in on a populist platform two years ago was in evidence when his Sweet Smell of Service party suffered dramatic losses in municipal elections last December.

It is Ahmadinejad’s apparent detachment from the economic realities facing ordinary Iranians that now threatens his position, according to critics who also argue that his nuclear obsessions have left the country isolated and vulnerable to attack.

Some rivals accuse him of using confrontation with the West to distract people from the mundane but pressing concerns of stagnant wages, skyrocketing prices and imminent petrol rationing, an extraordinary prospect in a country that earns £100m a day from oil revenues.

Every conversation here last week seemed to revolve around the imposition of petrol rationing on May 21. Subsidised petrol will rise from 800 riyals (about 4p) to 1,000 riyals (5p) per litre. Far worse in this sprawling traffic-choked city, only three litres a day will be available at that price. Ration cards will be issued and any purchase over the limit will be at a nonsubsidised rate that has yet to be decided.

“It is one of the most sensitive decisions ever taken in the history of the Islamic Republic of Iran,” said Saeed Laylaz, an Iranian economist. “There will be dissatisfaction, unrest and more inflation. At worst, there will be an explosion in the social structure.”

Iranians have already been hit by a 50% rise in fares last month. Shared taxis, the favourite way to get around town, rose from 1,000 riyals to 1,500 (8p) for the shortest journey. Every such increase counts in a country where a teacher is paid about £30 a week.

The mood on Tehran’s streets, where any expression of political opposition could land a protester in prison, is mutinous.

“The only good thing about the nuclear issue is that it seems it has brought so much pressure on this government that this might be the end of them,” said Shahla, 38, standing with bags of spring onions, radishes and tomatoes outside a greengrocer’s near Ahmadinejad’s old house in the eastern Tehran district of Narmak. She did not buy the cucumbers she wanted because they cost too much.

Shahla is no radical but a mother of two who works as a hairdresser. Her husband is a carpenter and they can barely make ends meet. “People are struggling to survive,” she said. “My children should be eating fruit, but it’s too expensive.” A woman in a black chador, the dress of the ultra-conserva-tive, stopped to listen. In the old days she would have been one of the unofficial guardians of the revolution and would have stopped the conversation. Instead, she chimed in. “The people’s blood is boiling,” she said, introducing herself as Miriam, an employee of the education department. “But we are strangled, we cannot speak.”

These are the people who voted Ahmadinejad into power and they are furious that their salaries remain pitifully low while the price of food rises at a rate unofficially estimated at between 20% and 40%. They feel betrayed and say they will not vote for him again.

Some Iranian analysts say Ahmadinejad’s theatrics have not only sent his popularity into freefall but have also earned the displeasure of Khamenei - who could remove him.

Such a radical move seems unlikely, not least because it might give the impression that Iran was bowing to western demands. But Ahmadinejad will face an uphill battle to win a second term, given the state of the economy and the impression that he is a demagogue.

The dark horse positioning himself to challenge the president is Mohamed Baqer Qalibaf, Ahmadinejad’s successor as mayor of Tehran.

Qalibaf, a former Revolutionary Guard now seen as a conservative pragmatist but who straddles both camps, is one of the few politicians earning praise in Tehran by concentrating on practical matters such as building parks and new pavements. In a contest with a mystic obsessed with nuclear matters, the practical man preoccupied with pavements and the price of bread may just prove to be the winner.

Former FBI man held

A former FBI agent who disappeared in Iran last month is being held by Revolutionary Guards in a “safe house” in Tajrish, northern Tehran, according to a source within the guard, writes Uzi Mahnaimi.

They want to swap Robert Levinson, 59, a private investigator from Florida, for Ali Reza Asgari, an Iranian general who vanished in mysterious circumstances in Turkey in February.

Levinson, who is said to be unwell, has apparently been interrogated by guards who intend to broadcast his testimony on television once Tehran acknowledges that it is holding him.

He disappeared on March 11 while on the island of Kish, an Iranian free trade zone where a visa is not required.

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