Moqtada al-Sadr has threatened to declare open war if the crackdown by Iraqi and US forces against his loyalists is not stopped.
The Iraqi Shia cleric said he was giving his last warning and his word to the Iraqi government to take the path of peace and stop violence 'against its own people'.
Otherwise, his statement continued, it will be a government of destruction.
'If it does not stop the militias that have infiltrated the government, then we will declare a war until liberation.'
He also lashed out at the Iraqi government's alliance with the US military.
'The occupation has made us target of its planes, tanks, air strikes and snipers. Without our support this government would not have been formed. But with its alliance with the occupier it (the government) is not independent and sovereign as we would like it to be,' the cleric said.
Iraqi and US forces have been engaged in fierce street battles with Shia militiamen since 25 March in Sadr's Baghdad bastion of Sadr City and in the southern city of Basra.
The firefights erupted after Prime Minister Nuri al-Maliki ordered assaults on Shia militiamen in Basra.
The crackdown triggered clashes across Shia areas of Iraq, including the sprawling district of Sadr City.
Hundreds of people have been killed and scores wounded since then.
Yesterday, at least 13 more people were killed in Sadr City, while Iraqi troops took control of a Sadr stronghold in Basra.
Students kidnapped
Nine university students and their driver have been kidnapped near Baquba, north of Baghdad.
The ten were abducted after gunmen stopped their vehicle at a fake checkpoint.
The students were returning to Diyala University after a weekend break.
The kidnapping comes two weeks after 40 students were seized by gunmen at a fake checkpoint near the northern city of Mosul.
They were held for several hours before security forces freed them.
