Amid speculation on a possible thaw in Iranian-US relations, prompted by America's response to the Bam earthquake, a powerful right-wing leader has mounted a bitter attack on the US and on President Bush.
Speaking at Friday prayers, Ayatollah Ahmad Jannati, who heads the powerful Council of Guardians, said the Americans were trying to exploit the disaster to seek relations with Iran.
Iranian hard-liners suspect American intentions
If anybody thought the goodwill generated by the American response to the Bam earthquake might create an immediate sea-change in Iranian politics, Friday prayers in Teheran was back to reality time.
Worshippers - and it is usually a hard-line attendance - chanted the time-worn slogan of Death to America, while Ayatollah Jannati, launched a bitter denunciation of Washington in general and the man he called "that damned Bush".
On the Bam earthquake, Ayatollah Jannati thanked the Iranian and international rescue teams but the Americans, he said, were politically motivated and were trying to exploit it for opportunistic reasons.
"Our answer is to slap you in the face and to say that for the paltry aid you sent we cannot forget our problems with you and extend the hand of friendship and relations," he said.
"If you're so full of compassion, why don't you go and help the Palestinians, whose earthquake you created?"
Ayatollah Jannati is one of the toughest hardliners, a man of great power.
He heads the Council of Guardians, a body which vets not only legislation but also candidates for general elections.
His deliberately offensive assault on President Bush and the Americans was presumably intended to scotch any hopes that the US response to the earthquake might help melt the ice between the two estranged countries.
But interestingly and unusually his remarks were not carried in the lunchtime bulletins of the main state television channel, which is regarded as a right-wing institution, and they were toned down in the official Iranian news agency account.
Pragmatic conservative Iranian leaders have apparently left open the possibility that the earthquake might help open the way to better relations.
This was the formula that took shape in November, when the mainstream of the clerical regime agreed to comply with the international community over Iran's nuclear programme, despite bitter opposition from the real hardliners.