ERBIL, Iraq/WASHINGTON (Reuters) - Iraqi Shi'ite militia fighters are tightening a noose around the Islamic State-held city of Falluja west of Baghdad as the first stage of a counter-offensive in the Sunni province of Anbar, likely to determine the course of the conflict in coming months.
Islamic State seized Anbar's capital Ramadi two months ago, extending its control over the Euphrates river valley west of Baghdad and dealing a major setback to Prime Minister Haider al-Abadi and the U.S.-backed army he entrusted with its defense.
While the government initially vowed to swiftly recapture Ramadi, it now appears to have turned instead to Falluja, a city located further downriver and closer to Baghdad, meaning supply lines for a counter-offensive would be less vulnerable.
Colonel Ali al-Yasiri, commander of Iraq's 4th armored regiment, 1st division, which is fighting near Falluja, said plans for a quick offensive to retake Ramadi were shelved in June after commanders concluded that Falluja would be "a dagger pointed at the army in Ramadi" unless it was tackled first.
"Our commanders gave us orders one week after losing Ramadi to regroup ... in order to launch a counter offensive to retake Ramadi," he told Reuters. "This decision failed to win support from all military commanders."
As the government seeks to claw back territory, Abadi has turned to the mainly Shi'ite Hashid Shaabi militia fighters who have proven more successful than the army on the ground.
In April, the militia recaptured the city of Tikrit, former dictator Saddam Hussein's home town on the Tigris river north of Baghdad. But until the fall of Ramadi in May, the government was reluctant to deploy the Shi'ite fighters west of Baghdad in the valley of Iraq's other great river, the Euphrates, where Sunni tribes have been hostile to outsiders for generations.
The army seems to be taking advantage of the extra capabilities offered by the militia umbrella group, which includes Iranian-backed elements. Yasiri welcomed the Hashid's involvement, saying the army had struggled unsuccessfully for 18 months to contain Sunni insurgents in Anbar.
Abadi and the army can also rely on U.S.-led air support, more closely coordinated since U.S. officers moved into a military base less than 10 miles (15 km) from Falluja and started overseeing training of Sunni tribal recruits there.
Jets and artillery have been pounding both Falluja and Ramadi, inflicting heavy daily casualties on militants and civilians alike according to medical sources.
Shi'ite militia figures say they will take the lead on the ground, not the army.
"Hashid forces are closing in on Daesh terrorists inside Falluja after seizing almost all supply routes around the city," said Muen al-Kadhimi, a senior aide to Hadi al-Ameri, commander of the Iranian-backed Badr organization, the most powerful of Iraq's armed Shi'ite groups.
Shi'ite fighters and army troops have made gains north of Falluja this week, although they faced heavy resistance from Islamic State fighters who sent car bombs to stem the advances. Authorities say they already control Falluja's eastern, southern and western approaches.
Tribal and insurgent sources in Anbar reported an Islamic State attack early on Friday in villages between Falluja and Ramadi, which lie about 40 km (25 miles) apart on the Euphrates. But their opponents insist the campaign to retake Anbar is on track.
"Now we are only 5 kilometers (3 miles) from the center of Falluja and the plan to liberate the city is going perfectly." said Kadhimi.
He confirmed the strategy of retaking Falluja before the provincial capital: "We can’t go to Ramadi first and leave our back exposed. This is why Falluja is a prior target."
Falluja saw the fiercest fighting of the U.S. occupation which followed Washington's 2003 invasion to topple Saddam Hussein, and has also been a center of Sunni hostility to the Shi'ite-led government in Baghdad.
Washington, which criticized the Iraqi military for allowing Ramadi to fall, has supported its decision not to rush to recapture it.
"The Ramadi campaign, which about a month ago was about to
be executed precipitously, has actually been, with our help... a very deliberate campaign," the top U.S. military officer General Martin Dempsey said this week.
Along with the shift in tactics after Ramadi's fall came recriminations, with Abadi sending his army chief of staff into retirement and suggesting the army's withdrawal in mid-May directly contravened instructions.
"If the orders had been carried out, Ramadi would not have
fallen," the prime minister said. Dempsey, welcoming the retirement of General Babaker Zebari, said there had been "issues up and down the chain of command" in the Iraqi military.
Yasiri, the army colonel, said army operations in Anbar had been troubled from the start.
"Troops were deployed in Anbar to fight insurgents since late 2013 and what was supposed to be a smooth operation to take out scattered terrorist groups turned out to be a war of attrition," he said. "With lack of military equipment, soldiers and effective air force, our troops started to lose initiative."
The loss of Ramadi was the army's worst defeat since Islamic State militants swept through north Iraq last summer, and pushed plans for an eventual offensive against the Islamists' northern stronghold Mosul further back.
While the army was forced on the defensive, militia leaders have moved into Anbar with their fighters. Photographs have also circulated purporting to show Qassem Soleimani, commander of Iran's Revolutionary Guards Quds Force, in the western province. Iran's support for the Shi'ite militia is uncomfortable for Washington.
Lawrence al-Hardan, a Sunni tribal sheikh from Anbar, said tribes had urged the army to drive Islamic State from Falluja well before the fall of Ramadi because "the masterminds of Daesh use Falluja as a launchpad in almost all attacks in Anbar."
"Until now I can't figure out why security forces failed to retake one inch of Falluja," he said.
But former general Jasim al-Bahadli said the army was not trained enough in guerrilla warfare to tackle Islamic State.
Only the Hashid Shaabi fighters, their skills honed by Iranian support and the experience some have of fighting in neighboring Syria, could defeat the hardline insurgents.
"Hashid is growing into an elite force, without which the army can’t win a war," he said.
Writing by Dominic Evans; Editing by Peter Graff