Britain, America, Israel and European leaders today cast doubt over President Ahmadinejad’s re-election victory as Iran faced a growing backlash at home and abroad.

Official results awarded Mr Ahmadinejad a thumping 63 per cent, but defeated opposition candidates have complained that at some polling centres results were announced before the ballot boxes were opened, and that in others more than 100 per cent of the electorate apparently turned out to vote.

The German Chancellor Angela Merkel said frankly today that there were signs of irregularities in the election, while Germany’s Foreign Minister summoned the Iranian ambassador for a dressing-down over the tactics employed by baton-wielding police against demonstrators who have taken to the streets of Tehran to say that the outcome of Friday's election was rigged.

“The actions of the Iranian security forces are completely unacceptable,” said Frank-Walter Steinmeier, in comments shown on German television.

Both Mr Steinmeier and Bernard Kouchner, his French counterpart, today urged Iran to hold a swift inquiry into claims of vote rigging.

“I asked today that the investigations demanded by the (Iranian) opposition be carried out,” Mr Kouchner said, after discussing the election with other EU foreign ministers in Luxembourg. Mir Hossein Mousavi, the leading opposition candidate, has appealed for an inquiry, dubbing the results a "charade"

Ehud Barak, the Israeli Defence Minister, said that the re-election of Mr Ahmadinejad - who denies the Holocaust, calls for the destruction of the state of Israel and is accused of trying to develop a nuclear bomb – was “bad news”.

“The triumph of the extremists is bad news, as any kind of victory of extremists should be defined,” Mr Barak told journalists at the Paris Air Show.

“I’m not sure if the results reflect the real will of the Iranian people.”

Joe Biden, the US Vice President, said: “There is an awful lot of questions about how this election was run.

“It sure looks like the way they are suppressing speech, the way they’re suppressing crowds, the way in which people are being treated, that there are some real doubts about that.”

He added that that America nonetheless stood by its offer to forge improved relations with Iran.

David Miliband, the British Foreign Secretary, echoed Mr Biden, calling for Tehran to rejoin international talks. "Our concern is above all for Iranian engagement with the international community," he said.

"We continue to await an Iranian answer to the very generous proposals that were made by the international community with respect to the Iranian nuclear programme. It's very important that that proposal is answered by Iranian willingness to sit down and negotiate. "

Mr Miliband said he was concerned at events in Iran over the weekend, and was following the situation carefully, but he drew back from calling for an inquiry. "I think it's for the Iranian people to choose their own government, it's up to the Iranian people to live up to their own standards, and up to the Iranian government to live up to the standards they proclaim."

Among Iran’s neighbours reaction was more favourable, with congratulations from Jalal Talabani, the Iraqi President, and Afghanistan’s leader Hamid Karzai, who called Mr Ahmadinejad’s re-election “a suitable selection".

International television networks, meanwhile, accused Iran of interfering in their efforts to report on the post-election violence, with a journalist for Spanish television claiming that the team had been expelled. Yolanda Alvarez of the RTVE public broadcasting network said in a radio interview that the Iranian authorities “have asked us to leave the country today".

The BBC said that the satellites it uses to broadcast BBC Persian television to Iran were being jammed. Peter Horrocks, the director of the BBC World Service, said it “seems to be part of a pattern of behaviour by the Iranian authorities to limit the reporting of the aftermath of the disputed election.”

Amnesty International called for an investigation into “the shocking scenes of violence meted out by the security forces".

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