The hardline cleric, known to be anti-U.S. occupation, said that the protesters have the right to demonstrate as long as they are peaceful, in a statement made from the holy Shiite city of Najaf.
Protesters have been holding rallies in the western desert province of Anbar and other Sunni strongholds for more than a week. The demonstrations follow the arrest of bodyguards assigned to the Sunni finance minister, Rafia al-Issawi, though they tap into deeper Sunni grievances of perceived discrimination by the government of Shiite Prime Minister Nouri al-Maliki.
Al-Sadr grudgingly backed longtime rival al-Maliki following elections in 2010, then last year joined Iraq’s minority Sunni Arabs and Kurds in calling for al-Maliki to resign.
Maliki looked to head off protests in Sunni areas of the country with a prisoner release even as he threatened to use state resources to “intervene” to end the rallies.
Maliki ordered the release of more than 700 female detainees, a key demand of demonstrators, the official appointed to negotiate with protesters, told AFP.
“The prime minister will write to the president to issue a special amnesty to release them”, Khaled al-Mullah said.
Mullah said of 920 female prisoners in Iraqi jails, 210 had been accused or convicted of terrorism-related offences and could not be released. But, he said, they would be transferred to prisons in their home provinces.
The remaining detainees, convicted on lower-level charges, would be released, he said. He did not give a timeframe for the process.
On Monday Maliki warned protesters blocking the highway to Syria and Jordan that his patience was running thin.
The demonstrators should “end their strike before the state intervenes to end it”, he said in an interview with the state broadcaster Iraqiya.
Addressing the protesters he said: “I warn you against continuing (blocking the highway), because this is against the Iraqi constitution”.
“We have been very patient with you”, he added.
The rallies began on Dec. 23, sparked by the arrest of at least nine guards of the Finance Minister Rafa al-Essawi, a Sunni Arab and a leading member of the secular Sunni-backed Iraqiya bloc. While it is part of Maliki’s unity government, the bloc frequently criticizes him in public.
Protesters in mostly Sunni areas of Iraq’s west and north have accused the Shiite-led authorities of using anti-terror legislation to target their minority community.