BAGHDAD -- Iraq vowed Tuesday to retake Anbar province -- now mostly held by the Islamic State -- by launching a large-scale military operation less than two weeks after suffering a humiliating defeat at the hands of the extremists in the provincial capital of Ramadi.
The operation, which Iraqi state TV said was backed by Shiite militias and Sunni pro-government fighters, is deemed critical in regaining momentum in the fight.
But as a sandstorm descended across the region, there was no sign of any major engagement against the extremists, who have been gaining ground in the province west of Baghdad despite U.S.-led airstrikes.
A Pentagon spokesman, Col. Steve Warren, said Iraqi forces have begun "shaping operations" and "security zone interactions," which he described as probing and reconnaissance actions that would precede any major combat in or around Ramadi.
The Iraqis have begun moving forward from their base at Habbaniyah, and IS fighters likewise are probing in the direction of Habbaniyah, Warren said. He added that he could not confirm that the Iraqi forces have surrounded Ramadi.
The Islamic State -- also known by the acronyms ISIS and ISIL, and Daesh in Arabic -- seized large parts of Anbar in early 2014 and captured Ramadi earlier in May. Iraqi forces, which had been making steady progress against the extremists in recent months with the help of the air campaign, scored a major victory in recapturing Saddam Hussein's hometown of Tikrit last month.
Elsewhere in Anbar province, the Islamic State group last week captured the Iraqi side of the key al-Walid border crossing with Syria. Those gains followed the IS seizure of the ancient town of Palmyra in Syria.
The launch of the operation in Anbar came only days after U.S. officials, including Defence Secretary Ash Carter, criticized Iraq's forces, saying its troops fled the IS advance on Ramadi without fighting back, leaving behind weapons and vehicles for the extremists.
Baghdad defended its troops and said preparations were underway for the large-scale counteroffensive in Anbar, involving Iranian-backed Shiite militias known as Popular Mobilization Units. That possibility sparked fears of potential sectarian violence in the Sunni-dominated province, long the site of protests and criticism of the Shiite-led government in Baghdad.
The Shiite militias chose a religious name for their campaign, deepening those worries and drawing criticism from the Pentagon. The Popular Mobilization Units have named it "Labaik Ya Hussein," which is Arabic for "I am here, Hussein" -- referring to a grandson of the Prophet Muhammad and one of the most revered figures of Shiite Islam.
Warren called the title "unhelpful," adding: "We've long said ... the key to expelling ISIL from Iraq is a unified Iraq that separates itself from sectarian divides."
Karim al-Nouri, a spokesman for the Popular Mobilization Units, said the name wasn't sectarian.
"This name has no sectarian dimension (or meaning) because all Iraqis, regardless of their sect or religion, love Imam Hussein," al-Nouri said.
A spokesman for Iraq's Shiite militias said the operation would "not last for a long time," and that Iraqi forces have surrounded Ramadi on three sides.
New weapons are being used in the battle "that will surprise the enemy," said Ahmed al-Assadi, who is also a member of parliament. He told reporters that another operation was underway north of the nearby province of Salahuddin.
Plans called for the forces in Salahuddin to move against Ramadi from its northeastern side, al-Assadi added.
The Anbar operation aims to cut off supply routes and recapture the outskirts of Ramadi first -- not the city itself, according to provincial councilman Faleh al-Issawi and tribesman Rafie al-Fahdawi.
They told The Associated Press there was ongoing fighting and airstrikes west and south of Ramadi on Tuesday, adding that more Sunni fighters will be armed starting Wednesday to fight the Islamic State.
The sandstorm complicated efforts to retake the city, al-Issawi said.
"There is zero visibility on the front lines and our men are highly concerned that they might come under attack by Daesh in such bad weather," he said.
Security forces and Sunni militiamen who had been battling the extremists in Ramadi for months collapsed as IS fighters overran the city.
The militants gained not only new territory 70 miles (115 kilometres) west of Baghdad, but also large stocks of weapons abandoned by government forces as they fled.
Carter said Sunday that Iraqi forces had "vastly outnumbered" the IS militants in Ramadi but "showed no will to fight."
Saad al-Hadithi, a spokesman for Prime Minister Haider al-Abadi, said Carter's remarks surprised the government and that he "was likely given incorrect information."
White House spokesman Josh Earnest defended Carter's remarks, saying the Iraqi government acknowledged that the setback in Ramadi was the result of a breakdown in command and planning. Earnest added that the Iraqi forces in Ramadi had not benefited from U.S. or allied training.
He praised Iraq's announcement it had launched a major military operation to drive Islamic State from Anbar, adding: "I think that is a clear indication of the will of the Iraqi security forces to fight. And the United States and our coalition partners will stand with them as they do so."
Gen. Qassim Soleimani, the head of the elite Quds forces in Iran's Revolutionary Guard who has taken on an advisory role with the Shiite militias, lashed out Monday at U.S. efforts. The Iranian daily newspaper Javan, seen as close to the Revolutionary Guard, quoted Soleimani as saying the U.S. didn't do a "damn thing" to stop the advance on Ramadi.
"Does it mean anything else than being an accomplice in the plot?" he reportedly asked, later saying the U.S. showed "no will" in fighting IS.
Al-Abadi had urged the Shiite militias to help retake Anbar province. The militiamen have played a key role in clawing back territory from IS elsewhere in Iraq, although rights groups and Sunni residents have accused them of looting, destroying property and carrying out revenge attacks -- especially after government forces recaptured Tikrit last month. Militia leaders deny the allegations.
The participation of the Shiite militias in the Anbar operation risks exacerbating tensions that arose amid retaliatory sectarian killings that roiled Iraq in 2006 and 2007. Distrust of the Shiite-led government runs deep in Anbar, where U.S. troops fought some of their bloodiest battles since Vietnam and only succeeded in rolling back militants when Sunni tribesmen and former insurgents rallied to their side as part of the Sahwa, or Awakening, movement in 2006. After the U.S. troop withdrawal, Sunni anger at Baghdad has grown steadily.
Associated Press writers Sameer N. Yacoub in Baghdad and Robert Burns and Jim Kuhnhenn in Washington contributed to this report.
