Websites of opposition leaders Mir Hossein Mousavi and Mehdi Karroubi have posted calls by their supporters to stage nationwide rallies on Sunday.

"We will confront them as per the law," Iran's Interior Minister Mostafa Mohammad Najjar was quoted as saying on state news agency IRNA when asked about Sunday's expected rallies.

"The agents of sedition and sedition leaders, who staged illegal rallies" on February 14 with the help of "monafeghin (hypocrites), monarchists, rascals and thugs, should know that the interior ministry will confront" them, Najjar added.

Kaleme.com and Sahamnews.org posted calls for Sunday gatherings to mourn the deaths of Sane'e Zhale, a Sunni Kurd, and Mohammad Mokhtari, a Shiite, who were slain on Monday in clashes with security forces.

The fatal confrontation erupted when opposition supporters took to Tehran streets protesting against the government.

The so-called Council for Coordination of the Green Movement Hope, which posted the call, said the Sunday rallies will also show "decisive support" to the stance taken by Mousavi and Karroubi in "continuing on the difficult path of freedom and human dignity."

Mousavi and Karroubi have steadfastly refused to acknowledge the presidency of Mahmoud Ahmadinejad and their rebellion has triggered one of the worst crises in the history of the Islamic republic.