A hardline cleric close to the Iranian regime demanded the execution of leading demonstrators yesterday as the opposition ended the week in disarray.

In a televised sermon at Friday prayers in Tehran, Ayatollah Ahmad Khatami called on the judiciary to “punish leading rioters firmly and without showing any mercy to teach everyone a lesson”. He said that those leaders were backed by the United States and Israel. They should be treated as mohareb — people who wage war against God — and deserved execution.

In a clear warning to all other dissenters, he declared: “Anybody who fights against the Islamic system or the leader of Islamic society, fight him until complete destruction.”

The Ayatollah claimed that Neda Soltan, the woman shot during a demonstration last Saturday, had been killed by fellow protesters because “government forces do not shoot at a lady standing in a side street”.

Ayatollah Khatami’s address came at the end of a week in which the regime has brutally suppressed all street protests and arrested hundreds of opponents for daring to challenge President Ahmadinejad’s re-election.

The Guardian Council, which oversees elections and is controlled by regime loyalists, said that it had found no major irregularities in the election on June 12, and described it as the “healthiest” since the Islamic Revolution of 1979. It offered the losing candidates the sop of a special commission but nobody believes that it will annul a result that has been unambiguously endorsed by Ayatollah Ali Khamenei, the Supreme Leader and Mr Ahmadinejad’s main sponsor.

Regime operatives appeared to have sabotaged the main website through which Mir Hossein Mousavi, the defeated candidate, communicates with his supporters. The former Prime Minister has not appeared in public for nine days and his movements are said to have been curtailed by a large, unwanted security force.

The regime’s ubiquitous security groups now break up even the smallest gatherings before they can gain critical mass. Its agents have become adept at spreading misinformation about when and where protests are taking place, and intimidating Tehranis with telephone calls warning them not to join rooftop protests at night. They have also shut opposition newspapers.

The regime blocked a day of mourning for the victims of the demonstrations that had been organised by Mehdi Karoubi, another of the defeated candidates, and pressured Mohsen Rezai, the fourth candidate, into dropping complaints about electoral fraud.

The opposition had planned to release thousands of green balloons over Tehran yesterday bearing the message “Neda you will always be in our heart”. The protest failed to get off the ground.

“The opposition is in retreat, pondering its next move,” an analyst in Tehran said. “People are demoralised to some extent and just don’t have the bounce in their step they had a week ago . . . The regime thinks it’s got them on the run and can finish them off.”

The most outspoken criticism of the regime is now coming from outside Iran. On Thursday President Obama called the regime’s suppression of dissent “outrageous”. He admitted that his hopes of opening a dialogue with Iran had been damaged but rejected Mr Ahmadinejad’s demand that he apologise for criticising the crackdown.

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