BAGHDAD, Jan 6 (Reuters) - Iraq's prime minister urged people in the besieged city of Falluja on Monday to drive out al Qaeda-linked insurgents to pre-empt a military offensive that officials said could be launched within days.
In a statement on state television, Nuri al-Maliki, a Shi'ite Muslim whose government has little support in Sunni-dominated Falluja, called on tribal leaders to drive out militants who last week seized key towns in the desert leading to the Syrian border.
"The prime minister appeals to the tribes and people of Falluja to expel the terrorists from the city in order to spare themselves the risk of armed clashes," read the statement.
Two local tribal leaders said meetings were being held with clerics and community leaders to find a way to persuade fighters from the Islamic State of Iraq and the Levant (ISIL) to quit Falluja and avert further bloodshed.
Maliki promised the army, stationed outside the city, would not attack residential areas in Falluja as his forces prepare an offensive that has echoes of U.S. assaults in 2004 on the city, some 40 km (25 miles) west of Baghdad's main airport.
Security officials said Maliki, who is also commander in chief of the armed forces, had agreed to hold off an offensive for now at least to give tribal leaders in Falluja more time to drive out the Sunni Islamist militants on their own.
"No specific deadline was determined, but it will not be open-ended," a special forces officer said of plans to attack.
"We are not prepared to wait too long. We're talking about a matter of days only. More time means more strength for terrorists".
ISIL, has emerged in Syria's civil war as an affiliate of the international al Qaeda network and a powerful force among Sunni Muslim rebels seeking to oust President Bashar al-Assad.
In Iraq, it has been tightening its grip on Anbar province, a thinly populated, mainly Sunni region the size of Greece, and on the area's main towns, strung along the Euphrates river. Its stated aim has been to create a Sunni state straddling the border into Syria's rebel-held desert provinces.
Some armed tribesmen from Iraq's once dominant Sunni minority have been fighting ISIL militants in the area since last week. But others baulk at taking sides with the Shi'ite government in Baghdad.
Two years after U.S. troops ended nine years of occupation, violence in Iraq underlines how civil war between Syrian rebels backed by Saudi Arabia and other Sunni powers on one side and Assad, an ally of Shi'ite Iran, on the other has inflamed a broader regional confrontation along sectarian lines.
The United States said on Sunday it would help Maliki fight al Qaeda but would not send troops back. An Iranian official offered similar help.
U.S. Secretary of State John Kerry, in a shift that reflects some recent rapprochement with Tehran, suggested on Sunday that Iran could play a role in forthcoming peace talks on Syria.
When Iraqi police broke up a Sunni protest last week in Ramadi, the Anbar capital, deadly clashes fanned tensions across the province that was the heart of the insurgency after the 2003 U.S. invasion that brought Shi'ite majority rule.
The tribes of Anbar helped turn the tide of that insurgency at its height in 2006, banding together and making common cause with U.S. troops to rout al Qaeda.
The group's resurgence has divided people in Anbar, where many accuse Maliki of shutting Sunnis out of power and being a pawn of Shi'ite Iran. Some sympathise with and support the Islamist militants, or are too fearful to move against them.
Others have vowed to help the government regain control.
"We are going to have an important meeting this evening and that will include some al Qaeda fighters in Falluja to convince them to leave the city and deprive Maliki of a pretext to push his army inside the city," said one tribal leader said.
"We should make al Qaeda fighters understand that their staying in Falluja will create rivers of blood".
Known as the "City of Mosques" and a focus for Sunni faith and identity in Iraq, Falluja is home to some 300,000 people and was badly damaged in two offensives by U.S. forces against insurgents in 2004.
In recent days, residents have been fleeing the town in droves to escape fighting as well as looming shortages of food, drinking water, and frequent power cuts.
"The situation in Falluja is getting worse. There are gunmen everywhere," said doctor Mohammed al-Nuaimi, a resident of the city who spoke to Reuters via telephone as he packed his belongings and prepared to leave.
"We can't tell who's a friend and who's an enemy. I lost my elder brother in 2005 -- he was killed by the Americans -- and now I see same scenario happening. I'm not ready to feel the pain again."
The militants have also received help in Falluja from disgruntled tribesmen who have joined forces with them.
Much of Iraq's U.S.-equipped army is drawn from the Shi'ite majority and faces recalcitrance if not outright hostility in Anbar, which covers about a third of the country's territory.
Across the border, al Qaeda fighters have also captured swathes of Syria and are battling with fellow Islamist brigades as well as government forces.
ISIL was formed last year through a merger between al Qaeda's Iraqi and Syrian affiliates and has claimed responsibility for attacks in both countries. It includes foreign jihadists in its ranks and among its commanders.
West of Ramadi on Monday, clashes broke out at dawn between militants and special forces helped by tribal fighters.
"This combat has been going on with a well-trained and a highly organised al Qaeda group," said the Iraqi special forces officer, adding there were foreign fighters among the militants. "When we defeat it, the balance of power in the whole of Anbar province will change". (Writing by Isabel Coles; Editing by Alastair Macdonald and Philippa Fletcher)