Iraqi cleric Moqtada Sadr on Saturday urged his followers to ramp up pro-reform rallies by setting up tents in front of Baghdad's 'Green Zone' and camping out until their demands are met.
He said in a statement that the sit-in outside the fortified area where the state's top institutions and many embassies are based would begin next Friday, on March 18.
"I make a historical call to every honest, reform-loving Iraqi to rise up and start a new phase in the peaceful popular protests," the statement said.
Sadr urged protesters to stay there for the 10 remaining days of an ultimatum he gave the government last month.
"Get ready and organise yourselves to establish sit-in tents. This is your time to root out corruption and the corrupt," he said.
A month ago, Sadr gave Prime Minister Haider al-Abadi a 45-day deadline to present the names of technocrats for a new government.
Abadi has been pushing for a government of technocrats in a bid to revive reform pledges that he made last year but have remained largely a dead letter.
Despite some of the ministers seen as the most corrupt being from his own political movement, Sadr has, with some success, attempted to make the new reform drive his own.
Sadrists have held a series of massive rallies in central Baghdad, with thousands turning out on Friday for the latest protest to press their demands.
The presence a week earlier of armed Sadr supporters outside the Green Zone - where Abadi's office, parliament and the US embassy are located - sparked intense security concerns.