The US military will transfer security control of Anbar province, scene of some of its bloodiest battles since the 2003 invasion, to Iraqi forces on September 1, the provincial police chief told AFP on Thursday.

"September 1 is the official date for the transfer of the security file of Anbar from US forces to the Iraqi military command," Tareq al-Dulaimi said.

"We've been ready for several months, and our forces are completely ready to take over responsibility," the police chief said.

The announcement came after US Marine General James Conways said on Wednesday that Iraqi security forces were now ready to take over responsibility for the province, Iraq's largest and a former bastion of Sunni Arab insurgents.

"The change in the Al-Anbar province is real and perceptible," Conway said in Washington.

Anbar will be the 11th of Iraq's 18 provinces to be handed over by the US-led coalition, which currently has 25,000 soldiers there, a reduction from 37,000 in February, according to US army figures.

The number of Iraqi soldiers has grown to 37,000 from just 5,000 three years ago.

The once-restive province west of Baghdad is home to the former flashpoint cities of Ramadi and Fallujah, where deadly clashes between insurgents and US troops flared repeatedly after the invasion.

Much of the success in restoring stability to the province is down to Sunni tribesmen and former rebels who in late 2006 formed groups called "Sahwa" or Awakening Councils to fight al Qaida jihadists.

Meanwhile, also on Thursday, Shiite leader Moqtada al-Sadr that he has suspended indefinitely the activities of his feared 60,000 strong Mahdi Army.

"The Mahdi Army suspension will be valid indefinitely and anyone who does not follow this order will not be considered a member of this group," said a statement issued by Sadr in the Shiite shrine city of Najaf.

"We have set a cultural programme for the Madhi Army and we have named it Al-Mumahidun (Supporters of the Mahdi), and everybody should abide by it and whoever does not agree with it will be expelled from the army," it added.

Sadr did not immediately explain his decision which came after he promised earlier this month to dismantle the once feared militia if a planned security pact between Baghdad and Washington provides for the withdrawal of US troops.

The two sides are still negotiating the planned pact that would govern US troop levels and allow them to operate after a UN mandate expires at the end of the year.

Iraqi Prime Minister Nouri al-Maliki said this week that they had agreed there would be no foreign forces in Iraq after 2011, setting a timeline for a US withdrawal.

Maliki stressed however that despite the progress, there were still points of disagreement crucial to both sides in the proposed security pact.

The White House has repeatedly echoed that no deal has been finalised.

Sadr ordered a six-month freeze in attacks on rival armed groups and US forces in August last year after allegations that his fighters had been involved in bloody clashes with security forces in the shrine city of Karbala.

He extended the freeze for a further six months in February.