Akbar Hashemi Rafsanjani, the influential former Iranian president, yesterday warned of the grave consequences for Iran of a possible US attack, in a public challenge to the leadership's handling of the crisis surrounding its nuclear programme.

Mr Rafsanjani was speaking during a visit to the holy city of Qom, where he was seeking to foster consensus among senior ayatollahs against the radical approach of Mahmoud Ahmadi-Nejad, the president.