Sadr said on Friday that he had decided to dissolve the Promised Day Brigade, an armed faction loyal to him, and to close its headquarters.
“We hope this step will become a start for dissolving the armed groups and to hand over weapons and close their headquarters,” Sadr added.
On Thursday, the Shia cleric urged paramilitary groups to purge what he called undisciplined members, and said non-state armed groups should hand in their weapons.
His remarks come after some Shia militias were accused of an attempt to kill Iraqi Prime Minister Mustafa al-Kadhimi by armed drone on November 7.
The militias are disputing the result of an October general election that handed them a crushing defeat and have also staged sit-ins in Baghdad which turned violent this month.
Sadr, who commands his own militia but opposes all foreign influence in Iraq is seen as the main Shia rival of Iraq paramilitaries.
He will likely have a big say in the formation of the next Iraqi government, a prospect that worries his main rivals, according to Iraqi officials and independent analysts.
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