TEHRAN (Reuters) - Iran arrested two leading opposition figures on Monday ahead of a planned nationwide anti-government rally, an opposition website said.

Defeated presidential candidate Mirhossein Mousavi attends a rally in support of him in Tehran June 15, 2009. REUTERS/Jamejam Online

Mirhossein Mousavi and Mehdi Karoubi had been forced to stay in their homes in the capital Tehran for more than two weeks. Mousavi’s daughters said on the Kaleme website they had been prevented from approaching his house since February 14.

“Sources say that they have been arrested and transferred to the Heshmatiyeh jail in Tehran,” the website said.

An unidentified judiciary official quoted by the semi-official Fars news agency denied the report.

“The reports about Mousavi’s and Karoubi’s arrests are false ... They are currently in their homes and some restrictions have been imposed on them to prevent their contacts with ‘suspicious’ elements,” the official told Fars.

The International Campaign for Human Rights in Iran, an advocacy group which has staff in the United States and Germany, said on Sunday the two leaders had been moved secretly from their homes, where they had been under virtual house arrest for calling on supporters to protest against the government.

Mousavi and Karoubi were confined to their homes after calling for a rally on February 14, when thousands of their supporters took to the streets. Two people were killed and dozens arrested during the banned rally.

Both men, who spearheaded protests against President Mahmoud Ahmadinejad’s re-election in June 2009, face calls from parliament to be arrested, tried and hanged for what government supporters say is their role in stirring “sedition.”

Mousavi and Karoubi deny the allegation, saying the pro-reform movement is still alive despite mounting pressure against its supporters.

Earlier this month, their supporters took to the streets for the first time since post-election protests were crushed at a rally in December 2009.

Opposition websites have called for a nationwide rally on Tuesday, Mousavi’s 69th birthday, to demonstrate support for Mousavi and Karoubi. Iranian authorities have warned the opposition against holding any “illegal” gathering.

The Iran Green Voice website said another demonstration was planned on March 15 if their voice was ignored.

Several Facebook pages have called for protests every Tuesday.