Iran’s Supreme Leader will officially endorse President Ahmadinejad’s re-election on Monday as the regime faces a fresh barrage of protests — this time over the “show trial” of more than 100 opposition figures detained in the crackdown that followed the hotly disputed ballot.

Ayatollah Ali Khamenei will approve Mr Ahmadinejad’s second term during a televised ceremony in Tehran attended by other regime leaders, and on Wednesday the President will take the oath of office before Iran’s parliament. Seven weeks after the election, however, the regime is still battling to crush the resistance of millions of Iranians who believe that the poll was rigged.

On Saturday, in an apparent effort to deter further protests, it put scores of opponents on trial in Tehran’s Revolutionary Court, accusing them of conspiring with foreign powers to stage a revolution. Yesterday it added ten more defendants.

Many are senior officials in former reformist governments. They were dressed in grey prison uniforms, had lost weight and were denied access to lawyers.

The proceedings were closed, except to the state media, which later broadcast selected highlights, including the rambling “confessions” of various defendants including Mohammed Ali Abtahi, a former Vice-President.

Reading from a piece of paper, Mr Abtahi apologised for his previous claims that the election was fraudulent and accused Mir Hossein Mousavi, the defeated candidate, of conspiring with the former Presidents Mohammed Khatami and Ali Akbar Hashemi Rafsanjani.

All three men hit back. Mr Mousavi said the confessions “bore the hallmarks of medieval-era torture”, noted that the victims were “among those who gave great services to Iran in the past” and mocked the regime for expecting “a court, which itself is fraudulent, to prove there was no fraud committed in the election”. He added: “Soon we will see the trials of those who committed these crimes, the torturers and interrogators.”

Mr Khatami said that such “show trials” violated the constitution, the law and the rights of Iranian citizens, and undermined the entire political system. Mr Rafsanjani said the allegation that the trio had plotted against the regime was a “sheer lie”, and asserted that the extraction of dubious confessions undermined the foundations of the government.

Some conservatives joined the criticism. In a letter to the head of the judiciary, Mohsen Rezai, another defeated presidential candidate and a former Revolutionary Guards chief, said that those members of the security forces who “trampled on the law” when they cracked down on protesters should also be put on trial.

Reformist newspapers openly ridiculed the proceedings, but analysts said that the sentences could range from short prison spells to execution, and that the regime appeared to be using the trials to warn that Mr Mousavi and Mr Khatami could also be made to take the stand unless they accepted Mr Ahmadinejad’s election.

“Evidence of Khatami and Mousavi’s treason unveiled,” was the headline in yesterday’s hardline Kayhan newspaper, a regime mouthpiece.

“The plot leaders are corrupt people whose unforgiveable crimes include killing innocent people and co-operating with foreign enemies. But trying and punishing the mid-ranking elements cannot be the end of story,” it said. “If the main instigators of unrest who are known are not confronted, they will continue conspiring.”

Hardline MPs agreed. “Those who issued statements and directed recent riots should be accountable for the bloodshed and go on trial,” said Mohammad Taghi Rahbar, a member of parliament’s judicial commission, who said Mr Mousavi and Mr Khatami were primarily to blame for the unrest.

The prosecution also named Shirin Ebadi, the human rights lawyer and Nobel laureate, as a conspirator. She has been travelling abroad, encouraging opposition to the regime, and risks arrest if she returns.

The trial resumes on Thursday, with the defendants divided into three groups: “planners”, “stooges of enemy powers” and “hoodlums”.

Tonight the Swiss Embassy, which represents US interests in Iran, is seeking to discover the fate of three American backpackers who were detained late last week after inadvertently crossing the border from the semi-autonomous Kurdish region of northern Iraq.

The Kurdish regional government said that the Americans had crossed into northern Iraq from Turkey on Tuesday at Zakho. They then travelled to Sulaimaniyah and on to the resort town of Ahmed Awaa, where they got lost during a hike and were detained by Iranian authorities.

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