Radical Shiite cleric Muqtada al-Sadr revealed Friday that he plans to create a powerful fighting force to battle what he calls "the occupiers" in Iraq.

In a statement read after Friday prayers in the holy Shitte city of Kufa, Al-Sadr called on his nearly 60,000-strong Mahdi Army militia to exercise restraint

"The resistance will be carried out exclusively by a special group which I will announce later," the statement reads, adding that "weapons will be in the hands of this group exclusively and will only be directed at the occupier," referring to American forces in Iraq.

Those who disobey "will not be with me," he warned. "We will keep resisting the occupier until the liberation or martyrdom."

Al-Sadr also called on his followers to help establish social services in Iraq's dominant Shiite community.

Al-Sadr spokesman Salah al-Obeidi told AFP the action was aimed at building a more comprehensive movement that could better serve its followers.

"Sadr's view is to take the Mahdi Army on the path of social and cultural activities, far from the military. He wants to reform it and limit its responsibility," he told the French news service.

Al-Sadr, a longtime antagonist of the U.S.-led coalition, said his new group will not direct its operations against Iraqis. "It will be banned from using arms against any Iraqis."

Al-Sadr, who is believed to be in Iran, has not been seen publicly since May 25, 2007, when he was in the Kufa mosque during Friday prayers. His aides refuse to divulge his whereabouts, triggering speculation that he is in Iran, AFP reported.

Following numerous bloody clashes with U.S. forces in which his militia reportedly suffered heavy casualties — including one in the Shiite city of Karbala during a major religious festival — al-Sadr last August suspended his militia's activities and called for a ceasefire.

Al-Sadr maintains that his fighters have held to the ceasefire, but Mahdi Army forces battled U.S. and Iraqi troops last March in Baghdad and other Shiite regions, resulting in heavy militant and civilian deaths.

The U.S. military long has maintained that al-Sadr's forces are armed, trained and funded by Iran, a charge Tehran denies.

The Associate Press contributed to this report.