Iraq's defence ministry on Saturday announced a 72-hour halt to military operations in the militant-held city of Fallujah, but new violence showed the weeks-long crisis remains far from resolved.

The announcement raises the possibility of negotiations to end the crisis, during which gunmen have also seized parts of Ramadi, capital of Anbar province, highlighting both the reach of militants and the weakness of security forces.

While the loss of control in the two Anbar cities has posed a major challenge for Prime Minister Nuri al-Maliki's government, a successful resolution to the crisis could give the premier a boost ahead of parliamentary polls scheduled for April.

"Military operations taken against selected terrorist organisation targets in Fallujah have been stopped for a period of 72 hours" starting from the night before, the defence ministry said in a statement.

The decision was taken "in response to goodwill and frequent communications with the forces of good and people calling for peace, and to stop the bloodshed in Fallujah," it added.

Security forces have carried out shelling and strikes inside Fallujah, just a short drive from Baghdad, and periodically clashed with gunmen in the area.

Violence on Saturday showed the crisis in Anbar is far from over.

Six soldiers were wounded in clashes with gunmen in an area east of Fallujah, while a suicide bomber detonated an explosives-rigged vehicle near an army convoy west of Ramadi, killing six people and wounding four.

The defence ministry's ceasefire announcement comes a week after Maliki visited Ramadi for talks with provincial officials and the leaders of powerful local tribes.

The Iraqi government has also pledged compensation for Anbar residents whose property was damaged in the violence, and training for tribesmen who fought on the side of security forces.

The measures were the just the latest aimed at placating Anbar province residents, and Iraq's Sunni Arab minority, who complain of marginalisation by the government and of being unfairly targeted by heavy-handed security measures.

The crisis in the desert province of Anbar erupted in late December when security forces dismantled Iraq's main Sunni Arab anti-government protest camp just outside Ramadi.

Anti-government fighters subsequently seized all of Fallujah and parts of Ramadi, to its west.

It is the first time anti-government forces have exercised such open control in major cities since the peak of the deadly violence that followed the US-led invasion of 2003.

More than 370,000 people may have been displaced the violence in Anbar, according to the UN.

- Troops retake northern area -

The Fallujah ceasefire came after a localised version of the Anbar crisis in the Sulaiman Bek area, north of Baghdad, was said to have ended.

Militants had seized part of the Sulaiman Bek area, which includes a town of the same name and several villages, on February 13, setting off a cycle of clashes in which dozens of people were killed.

On Saturday, local official Talib al-Bayati said soldiers and police had been fully in control of the area since Friday, and the army was reinforcing it with watchtowers and sand barriers.

Security forces were preventing residents who fled the violence from returning to their homes, he said.

Violence in Iraq has reached a level not seen since 2008, when the country was emerging from a period of brutal sectarian killings.

Attacks in four provinces north of Baghdad killed eight people on Saturday, among them five security forces members.

More than 590 people have been killed in violence so far this month and upwards of 1,550 have died since January 1, according to AFP figures based on security and medical sources.