Iran's President Ahmadinejad accuses foreign governments of interference
The White House has accused Iranian President Mahmoud Ahmadinejad of seeking to blame the US for unrest following Iran's disputed election.
The US replied one day after Mr Ahmadinejad was sharply critical of President Barack Obama for condemning Iranian violence against protesters.
Tehran's leadership has accused foreign governments of fuelling the protests.
The Group of Eight foreign ministers, meeting in Italy, said they "deplored" the post-election violence in Iran.
In a statement, they urged Iran "to respect fundamental human rights" and settle the crisis "through democratic dialogue and peaceful means".
BBC News, Tehran
The Guardian Council is due to give its definitive verdict on Sunday.
But the remarks by its spokesman are yet another indication that it will be a formality.
The question though is whether the fracture in the ruling elite that this crisis has caused will heal.
When you ask Iranians about the way this might go, a phrase keeps cropping up. They say it might seem quiet to an outsider but there is fire below the ashes.
Earlier, Iran's Guardian Council said it had nearly finished examining the allegations of vote-rigging and had found no irregularities.
"We have had no fraud in any presidential election and this one was the cleanest election we have had," the electoral body's spokesman, Abbasali Kadkhodai, told the Irna news agency.
"I can say with certainty that there was no fraud in this election."
The BBC's Jeremy Bowen in Tehran says the comments are yet another sign that the Guardian Council's definitive verdict about the alleged election fraud - due on Sunday - will be a formality.
Supreme Leader Ayatollah Ali Khamenei has already said several times that the result is fair and will stand.
Meanwhile, another senior Iranian hardline cleric said in his Friday sermon that the leaders of the protests should be dealt with "severely and ruthlessly".
"I want the judiciary to... punish leading rioters firmly and without showing any mercy to teach everyone a lesson," Ahmad Khatami told worshippers at Tehran university in comments broadcast nationwide.
War of words
In Washington, White House spokesman Robert Gibbs said Iran's president was attempting to deflect attention from events at home.
"There are people in Iran who want to make this not about a debate among Iranians in Iran, but about the West and the United States.
"I would add President Ahmadinejad to that list of people trying to make this about the United States," Mr Gibbs said.
He was speaking in response to an angry statement made by Mr Ahmadinejad on Thursday in which Mr Obama was told to avoid "interfering in Iran's affairs".
"Our question is why he fell into this trap and said things that previously [former US President George W] Bush used to say," Mr Ahmadinejad was quoted as saying by the semi-official Fars news agency.
Despite the increasingly pointed rhetoric, the substance of the Obama policy towards Iran remains unchanged, says the BBC's Richard Lister in Washington.
The US regards its main priority as addressing Iran's nuclear programme and its support for militant groups, and Mr Obama has made clear repeatedly that the offer of talks with Tehran is still on the table, our correspondent adds.
Some Western nations are continuing to criticise Iran's handling of the crisis.
Tensions between Iran and the UK are already strained after Tehran accused Britain of inflaming the protests - charges London denies.
"We deplore post-electoral violence which led to the loss of lives of Iranian civilians," the statement from the meeting of G8 foreign ministers in Trieste said.
"We call on the Iranian government to guarantee that the will of the Iranian people is reflected in the electoral process," it went on.
The BBC's Duncan Kennedy in Trieste said it took many hours of discussions to find the right choice of words acceptable to all the ministers.
The strength of the wording was more muted than some had hoped for because of opposition from Russia, who said Iran should not be isolated.
In Iran itself, defeated presidential candidate and protest figurehead Mir Hossein Mousavi on Thursday accused those behind the alleged "rigged" elections of being responsible for the bloodshed during the protests.
He complained of "complete" restrictions on his access to people and a crackdown on his media group.
At least 25 people - including eight members of the pro-government Basij militia - are reported to have been killed and dozens more wounded in the protests since the disputed election on 12 June.
The figures cannot be verified due to severe reporting restrictions inside Iran.
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