Iraqi Shi'ite cleric Moqtada al-Sadr on Saturday threatened "open war" with the government unless it chose what he called the "path of peace".

The statement from the populist Sadr ratchets up the tension between the cleric and Prime Minister Nuri al-Maliki. Maliki has launched a crackdown on Sadr's Mehdi Army militia and threatened to bar his mass movement from political life.

"I'm giving the last warning and the last word to the Iraqi government - either it comes to its senses and takes the path of peace or it will be the same as the previous government," Sadr said, referring to Saddam Hussein's fallen regime but without elaborating.

The cleric added: "If they don't come to their senses and curb the infiltrated militias, then we will declare an open war until liberation."

Sadr's movement accuses other Shi'ite parties of infiltrating their militias into the Iraqi security forces.