Iran has banned an ally of the country's opposition leader Mirhossein Mousavi from leaving the Islamic state, the official IRNA news agency reported on Saturday.
EDITORS' NOTE: Reuters and other foreign media are subject to Iranian restrictions on their ability to report, film or take pictures in Tehran.
Abolfazl Fateh, head of Mousavi's media office, said the ban would not change his political stance, adding he was banned from leaving Iran because of his role in post-election developments.
Such pressures can not push people like me to change our political stances, he told IRNA. The imposed ban will not change my political views.
Iranian authorities have used a combination of warnings, arrests and the threat of police action over the last week to drive mass rallies off Tehran's street with smaller gatherings dispersed with tear gas and baton charges.
State media have said 20 people were killed in violence since the June 12 election -- won by hardline President Mahmoud Ahmadinejad -- and authorities accuse Mousavi of responsibility for the bloodshed. He says the government is to blame.
The state-run Iran newspaper said Fateh, who had been studying for a doctorate in Britain, was banned from leaving the country because of his involvement in post-election developments.
Mousavi has called for an annulment of the vote because of election rigging.
The semi-official ILNA news agency said Mousavi urged the Interior Ministry to allow a rally by his supporters at Azadi square in southwest Tehran. No date was mentioned in the report.
Iran's top legislative body has said it found no major violations in the presidential election which it described as the healthiest since the 1979 Islamic Revolution, but said 10 percent of ballot boxes would be recounted.
Tehran streets were calm on Saturday and life was back to normal.
The establishment has made it clear it had no intention of holding a new election and has set up a special court to deal with hundreds of detained protesters. A hardline Iranian cleric has called for the execution of leading rioters.
Group of Eight powers on Friday deplored violence stemming from the disputed presidential election in the world's fifth biggest oil exporter but held open the door for Tehran to take part in talks on its nuclear program.
Iran's foreign Ministry on Saturday rejected the call by the group as hasty interference and insisted the election was fair. The group is expected to deal with serious issues faced by its members and the international community, said Foreign Ministry spokesman Hassan Qashqavi, IRNA reported.
U.S. President Barack Obama on Friday praised the bravery of Iranians who protested against the disputed election in the face of outrageous violence.
Ahmadinejad repeated his call to Obama on Saturday to not interfere in Iran's state matters.
While Obama talks about change why is he following (former U.S. President George W.) Bush's path and interfering in our state matters, he told a conference in Tehran, IRNA reported.