BBC News reports:
Iranian opposition leader Mehdi Karroubi has been put under house arrest, his official website says.
Security officials at the premises say the measures will last until next week, it adds. No one is being allowed to enter the house except his wife.
Mr Karroubi and Mir-Hossein Mousavi, another opposition leader, had called for a rally on Monday to support the popular uprisings in Egypt and Tunisia.
The authorities refused permission, calling it a political move.
Although Iran’s establishment supports the Egyptian popular protests, a spokesman for Iran’s judiciary said on Wednesday that Iranians should show their solidarity by taking part in official rallies this Friday to commemorate the anniversary of Iran’s revolution.
Choosing another day to hold a rally means that the opposition leaders “wish to be in a separate front and will create divisions”, he told a news conference in Tehran.