Tehran would prefer Barack Obama to be elected as the next US president in the November 4 poll, Ali Larijani, the speaker of Iran's parliament, has said.

"We are leaning more in favour of Barack Obama because he is more flexible and rational [than rival John McCain], even though we know American policy will not change that much," he said during a visit to Bahrain on Wednesday.

How to deal with Iran and the crisis over its nuclear programme has been one of the central foreign policy issues in the US election.

Obama, the Democratic presidential nominee, has spoken about holding talks with the Iranian leadership "without precondition", a stance which has been ridiculed by McCain, his Republican rival.

Financial crisis

Washington severed ties with Iran in 1980 - in the wake of its Islamic revolution - and George Bush, the current US president, famously denounced the country as part of an "axis of evil".

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Larijani also said the United States is now too busy dealing with a financial crisis to consider attacking Iran over the nuclear programme.

"The risk was low before," he said. "But now I am 100 per cent certain that the United States will not unleash a war against Iran.

"The economic crisis has cost the United States $1,400bn and Washington is working to resolve its internal problems and not a war."