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By Ahmed Rasheed
BAGHDAD, Jan 7 (Reuters) - The Iraqi army deployed tanks and artillery around Falluja on Tuesday, security officials said, as local leaders in the besieged city urged al Qaeda-linked militants to leave in order to avert an impending military assault.
Security officials and tribal leaders have said that Prime Minister Nuri al-Maliki agreed to hold off an offensive to give people in Falluja time to push the militants out. But it is not clear how long they have before troops storm the town, close to Baghdad, where U.S. forces fought notable battles a decade ago.
"Tribal leaders appealed to the prime minister to halt the attack and stop shelling Falluja," an Iraqi special forces officer told Reuters. "We've done our part of the deal. Now they should do theirs. If not, a quick offensive is coming."
Fighters from the Islamic State of Iraq and the Levant (ISIL), an al Qaeda affiliate also active across the border in Syria, overran police stations in Falluja and another city in Iraq's western Anbar province last week.
Many in Iraq's once dominant Sunni Muslim minority, the main group in Anbar, share ISIL's enmity toward Maliki's Shi'ite-led government. But some tribal leaders in the province have been trying to steer a middle course between the two.
Late on Monday, tribal leaders from Falluja met and decided to set up a new local administration to run the city and appointed a new mayor and police chief. One Sunni tribal leader in the city told Reuters: "We are sending a clear message to the government - 'go ahead and fight al Qaeda outside Falluja and we ourselves will deal with the issue inside the city'."
"If the army attacks Falluja to fight a handful of al Qaeda elements, that will have dire consequences by triggering endless violence," he added, warning that bloodshed could spread to other Sunni districts of Iraq.
Iraq's U.S.-equipped armed forces have killed dozens of militants in recent days in shelling and air strikes, officials say. The scale of casualties among civilians, the security forces and tribal fighters is not yet clear.
Iraqi security forces backed by tribal fighters regained control in the centre of Anbar's provincial capital Ramadi on Monday, another special forces officer said. Clashes continued in the surrounding areas on Tuesday, he added. In the city centre, government offices, hospitals and markets reopened.
Baghdad political analyst Ahmed Younis said Maliki, whose prospects of a third term in a parliamentary election due in April have been dented by bombings and other violence across the country, would seize an opportunity to show himself as an assertive leader by taking the fight in Anbar to the militants.
"The Falluja battle is a matter of when and not if," said Younis. "Victory for Maliki will not be certain without clearing out Falluja, and for him it's al matter of survival.
"His message to voters will be: the strongest man is your best choice."
It is unclear how many fighters ISIL has in Falluja, or how much support it might have from residents, making it hard to predict the course of any offensive by Iraqi troops.
In late 2004, more than 10,000 U.S. troops fought weeks of street battles with several thousand insurgents in the city, 40 km (25 miles) west of suburban Baghdad.
ISIL appears to have much smaller forces and many may choose to slip away if faced with an all-out army assault.
The violence has underlined how civil war in Syria has inflamed a broader confrontation across the Middle East between Shi'ite Iran, the main ally of President Bashar al-Assad, and Sunni powers like Saudi Arabia, which back the Syrian rebels.
The United States said on Monday that it would speed up deliveries of military hardware, including drones and missiles, to Iraq. It has ruled out sending back troops, two years after Washington ended a near-decade-long occupation.
Maliki, who rose to power in the electoral system installed after the U.S. invasion toppled the Sunni Saddam Hussein, has maintained ties with the United States while also staying close to Washington's adversaries, Iran and Assad.
During the anti-American, anti-Shi'ite insurgency that raged in Anbar following the 2003 invasion, local tribes eventually rose up against al Qaeda, stifling its influence. But the international movement has regained ground in western Iraq in the past year, helped by foreigners coming from Syria.
ISIL has for some months been tightening its grip on Anbar, a thinly populated region the size of England, with the stated aim of creating a Sunni religious state straddling the border into Syria's rebel-held eastern desert provinces.
The exact relationship between ISIL fighters in Syria and Iraq is not clear, although they describe themselves as part of the same group. ISIL has been fighting fellow Islamists in Syria for the past week, losing ground and men to rival groups who say they oppose ISIL's approach and foreign leadership.
The governor of Anbar, Ahmed Khalaf, told Reuters that ISIL's problems in Syria explained an upsurge in violence in western Iraq. He said: "When the al Qaeda groups come under pressure in Syria, they flee to safer havens." (Writing by Isabel Coles; Editing by Alastair Macdonald)