Iran's President Mahmoud Ahmadinejad has called for leaders of the protests that followed his disputed re-election in June to be dealt with decisively, BBC reported.
A number of senior opposition figures are currently on trial in Tehran accused of conspiring with foreign powers to organise the unrest.
Iran's Supreme Leader Ayatollah Ali Khamenei said on Thursday there was no proof to this accusation.
Iran's opposition claims widespread vote fraud during the election.
"The leaders and the main elements involved in the [post-election protests] should be dealt with most seriously," Mr Ahmadinejad said in a speech before thousands of people before Friday prayers at Tehran University.
"Those who have organised [the protests], provoked and implemented the desires of the enemy should be dealt with decisively," he said in the speech, also broadcast live on state radio.
There were mass protests in Tehran after Mr Ahmadinejad was declared winner with 63% of the vote.
Opposition leaders say dozens of people were killed and hundreds arrested during the unrest.
Trials are taking place of some of those allegedly involved in the unrest, but they have been dismissed by critics as show trials.
Ayatollah Khamenei's remarks seem intended to reduce tensions over the disputed election and its aftermath, correspondents say.
"I do not accuse the leaders of the recent incidents to be subordinate to the foreigners, like the United States and Britain, since this issue has not been proven for me," said Ayatollah Khamenei in a statement read out on Iranian television.
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