Iraqi Prime Minister Nuri Al Maliki has ordered a nationwide freeze on raids against suspected Shi'ite militants.

Maliki said he was allowing time to those wanting to surrender their weapons after fierce clashes between his security forces and Shi'ite militiamen last week killed at least 700 people, according to a UN report.

'To give space and an opportunity for those who are remorseful and are willing to give up their weapons, all pursuits and raids in all areas will be stopped. Those who take up arms will face the law,' the Iraqi Premier said in a statement.

On Thursday, Maliki had threatened a crackdown on Moqtada Al Sadr's Mahdi Army strongholds in Baghdad.

Sadr called for a mass rally in Baghdad on Wednesday against the US forces in Iraq. It will mark the fifth anniversary of the overthrow of Saddam Hussein's regime.

'This demonstration is not limited to the Sadr movement. We want all Iraqis to take part,' a spokesman for Sadr's office said. Mahdi Army supporters spilled on to the streets in Baghdad to denounce Maliki and demand that US troops quit their areas.