Iran's powerful Guardian Council today offered a partial recount of disputed ballot boxes from last week's presidential election after claims that massive fraud ensured the re-election of the hardliner Mahmoud Ahmadinejad.

The move by the country's highest legislative body appeared to be the first concession to the opposition after hundreds of thousands joined the largest street protests since the Islamic Revolution of 1979.

But many portrayed it as a ploy by the mullahs to buy time before their formal endorsement of Mr Ahmadinejad's landslide win. A senior reformist ally of the defeated candidates Mir Hossein Mousavi and Mehdi Karoubi said that they wanted a full re-run off the election rather than a recount of "a few ballot boxes".

Meanwhile, Tehran was braced for another day of conflict after the Islamic regime called a rally against Mr Mousavi at the same venue where the Mousavi camp had called its own gathering just an hour later.

At least seven civilians were killed yesterday in clashes when members of the Basiji militia, a force of young Islamic hardliners, started shooting when their post came under attack during a mass rally that drew hundreds of thousands of people onto the streets of Tehran.

State radio said that the post came under attack at the end of what it called an "illegal" demonstration.

"Some thugs in an organised and coordinated action, attacked and vandalised a number of public and government buildings," it reported. "A military post was attacked with the intention of looting its weapons. Unfortunately, seven of our citizens were killed and a number of them injured."

The death toll may actually have been higher. A nurse at western Tehran’s Rasoul Akram hospital said that 28 people with "bullet wounds" had been brought in last night, of whom eight had died.

Meanwhile, Mr Ahmadinejad showed his contempt for the protests by visiting the Russian city of Yekaterinburg for a regional summit where his re-election was effectively endorsed not just by his hosts but other nations attending including China, India and Pakistan.

"It’s quite symbolic that the Iranian president arrived in Russia on his first foreign visit since re-election," Sergei Ryabkov, the Deputy Foreign Minister, told reporters in a briefing at the Shanghai Cooperation Organisation summit, at which Iran has observer status.

"We welcome the fact that the elections have taken place, and we welcome the newly re-elected Iranian president on the Russian soil."

Mr Ahmadinejad had originally been scheduled to arrive at the conference yesterday and was forced to call off bilateral talks with his Russian counterpart Dmitry Medvedev. Taking the floor at one of the summit meetings, Mr Ahmadinejad made no reference to the crisis at home, instead baiting the United States for its economic woes.

Yesterday's demonstrations saw hundreds of thousands on the streets and Mr Mousavi's supporters were due to flood into Tehran's Vali Asr Square at 5pm (1230 GMT).

The Islamic Propagation Council, one of the regime’s organs, issued a statement calling for a pre-emptive demonstration at the same square a couple of hours earlier.

"The ill-wishers of the Islamic revolution who cannot see a developed Iran are misusing the gatherings of some candidates, vandalising public property and attacking military centres, the police and the Basij with weapons," it said.

"It is time for the alert Iranian people to separate from the path of those who belong to deviant and violent currents and to foil their plots."

According to the official figures, Mr Ahmadinejad won a massive 24.5 million votes in Friday's election against 13.2 million for Mr Mousavi. Mohsen Rezai, the former head of the elite Revolutionary Guards, came third with 678,240 votes or 1.73 per cent, while the reformist Mehbi Karroubi, a former parliamentary speaker, trailed with 333,635 votes or 0.85 percent.

It is not just Mr Ahmadinejad's margin of victory that has cast doubt on the result, however, but the speed with which 39.1 million votes were counted – and the fact that the incumbent enjoyed a two-to-one lead even in his opponents' political strongholds.

In his first public comments on the election, President Obama said last night that he was "deeply troubled" by the violence in Iran, but said that it was up to the Iranians to "make a decision about who Iran's leaders will be".

"I think that the democratic process, free speech, the ability for folks to peacefully dissent, all those are universal values and need to be respected," Mr Obama said.

"Whenever I see violence perpetrated on people who are peacefully dissenting, and whenever the American people see that, I think they’re rightfully troubled."

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