TEHRAN: Iran's former president Mohammad Khatami on Wednesday dismissed confessions made by his aides at a Tehran trial of people arrested for opposing the re-election in June of Mahmoud Ahmadinejad.

"These kinds of comments are invalid... these claims are utter lies and hold no truth," Khatami said in a statement posted on his website.

"It is better for the officials to prevent such illegal and counter-religious acts, as they will hurt the Islamic republic's regime."

On Tuesday, around 20 people were put on a mass trial in a revolutionary court in Tehran on charges of masterminding post-election unrest and plotting a "soft coup."

Several defendants were Khatami aides during his presidency between 1997 and 2005.

One prominent aide, reformist Saeed Hajjarian who has been under house arrest since his detention on June 16, was also in court and apologised for "huge mistakes" he said he committed in the aftermath of the election.

The prosecution claimed Hajjarian had connections with British intelligence and the Soros Foundation which planned to launch a "velvet revolution" in Iran.

In other testimony, Iranian-American scholar Tajbakhsh, who was also in the dock, said Khatami had personally met George Soros in 2006 in New York along with Mohammad Javad Jarif, then Tehran's ambassador to the United Nations.

Khatami also dismissed Tajbakhsh's comments.

Iranian officials in 2007 accused the Soros Foundation of being in cahoots with an alleged US government drive to topple Iran's Islamic regime, a charge vehemently denied by the foundation.

Tajbakhsh was detained in Iran in 2007 for working with the Soros Foundation.

Iran has already staged mass trials of around 140 people on charges linked to the massive demonstrations and street violence that followed Ahmadinejad's hotly disputed victory in the June 12 presidential election.

His re-election triggered massive street protests in Tehran by supporters of his main rival Mir Hossein Mousavi and other defeated candidates, and set off political turmoil that has shaken the very pillars of the Islamic regime.

The trials have intensified the political turmoil gripping Iran as Ahmadinejad awaits a vote of confidence in parliament for his 21-member cabinet.