BEIRUT — A Kurdish-led force fighting the Islamic State group with the support of U.S. troops will close in on the extremists' de facto capital Raqqa within a few weeks, but the battle for the city will be difficult, a U.S. military official said Thursday.
Air Force Col. John Dorrian said the U.S. force consisting of a couple of hundred Marines that arrived in the region south of the Syrian-Turkish border on Wednesday will not have any frontline roles but will provide artillery fire to support the advance of the Kurdish-led Syrian Democratic Forces.
"The intent of their presence is to provide all-weather fire support, artillery fire to support their advance as they continue the isolation of Raqqa," he said. "This is just some added fire power that will be very difficult for the enemy to deal with."
The deployment reflects Washington's deeper involvement in Syria under the administration of President Donald Trump and thrusts the U.S. further into a difficult diplomatic entanglement.
Dorrian told The Associated Press by telephone that the U.S.-backed force will close in on Raqqa within a few weeks and warned that the battle for the city will likely be difficult as the extremists are well dug in. He said a complicating factor is that the U.S. does not have a partner government to work with in Syria as is the case in Iraq.
The U.S. already had some 500 advisers working with the Syrian Democratic Forces in addition to a force of 400 that arrived more recently, Dorrian said. He said the troops include U.S. Army Rangers already in Syria.
The SDF, a coalition of Kurdish, Arab and Christian fighters, has been the most effective force fighting IS in Syria. The SDF has been on the offensive in the Raqqa area since November under the cover of airstrikes by the U.S.-led coalition with the aim of eventually besieging the city before storming it.
Dorian said the SDF "made excellent progress and the enemy hasn't been able to stop them from doing the things that they set out to do." He added that SDF fighters have so far captured about 6,400 square kilometres (2,471 square miles) of terrain from IS.
"That's excellent progress," Dorrian said, adding that SDF fighters have also cut many supply lines used by IS to try to either escape from the city "or to have fighters leave the area and conduct terrorist operations elsewhere away from Iraq and Syria."
Dorrian said the SDF will need a "few more weeks" to completely isolate Raqqa and a decision will be made about the timing "of the liberation battle to begin."
The SDF recently withdrew from areas near its bastion Manbij, west of Raqqa, to make room for the Syrian military to deploy last week. Manbij lies 70 miles (113 kilometres ) northwest of Raqqa.
"There is a clear co-ordination between the Syrian army and Kurdish forces," Syrian lawmaker Omar Osse told the AP Thursday.
But the Syrian government is a pariah to Western states, and Damascus has never approved the presence of their militaries on Syrian soil.
"Any presence of U.S. forces or other forces on the Syrian land, without co-ordination with the Syrian state, is considered a flagrant violation of the Syrian sovereignty," said Osse.
The Marine deployment also risks antagonizing U.S.-NATO ally Turkey. The SDF is led by the main Kurdish militia the YPG, which Turkey says is a terrorist organization.
Late on Thursday night, Syria's state news agency SANA quoted an unnamed military official as saying that Turkish troops shelled Syrian army positions near Manbij killing and wounding several troops. The report gave no further details and there was no immediate comment from Turkey.
The incident is likely to increase tensions between Damascus and Ankara, which has been a main backer of opposition forces against the government.
Earlier on Thursday at least 20 civilians, including some children, were killed in suspected U.S.-coalition airstrikes on a village east of Raqqa, activists said.
The Britain-based Syrian Observatory for Human Rights, however, said the strikes occurred before dawn Thursday and killed 23 people, including eight children. The activist group Raqqa is Being Slaughtered Silently said at least 20 people were killed.
It was not possible to reconcile the two accounts — the Islamic State group maintains a tight grip on communications from its territory. The Observatory and RBSS get their information from closely guarded local contacts.
Russian and Syrian aircraft are not known to operate in the area, according to the Observatory. The group said U.S.-led coalition aircraft were believed to behind the attack.
The coalition did not confirm the strikes and there was no immediate indication which nation's aircraft were involved.
Associated Press writer Albert Aji in Damascus contributed to this report.
Philip Issa And Bassem Mroue, The Associated Press