The pragmatic conservative cleric, who will on Friday go into a run-off against far right-winger Mahmood Ahmadinejad, also promised to create a national unity government if he is elected and warned Iran was at a “difficult crossroads”.

“I ask for your help to prevent extremism with your massive participation in the second round,” Rafsanjani said in a statement faxed to AFP.

He repeated allegations made by defeated reformist candidates that the first round of voting last Friday was ‘tarnished’ by ”organised action and intervention”.

Breaking his silence one day after the shock result was announced, Rafsanjani spoke of a “smear campaign against candidates, the unjust questioning of the achievements of the revolution ... and certain organised actions to orient the vote.”

“If this continues we do not know where it will lead,” he said.

“The vote in the first round shows the Iranian people do not share a single political belief and that the country cannot be ruled over by a single viewpoint,” said Rafsanjani.