ANKARA, Turkey (AP) -- Turkey's top diplomat said Tuesday that Washington has promised Ankara that U.S.-backed Syrian Kurdish forces will only be involved in a siege of the Islamic State group's stronghold of Raqqa in Syria but would not enter the city itself, once it is freed of IS militants.
The remarks by Mevlut Cavusoglu reflect Turkey's concerns over the expanding ground that Kurdish fighters have gained in Syria as they battle IS. Turkey considers the Syrian Kurdish militia to be a terror organization, saying it's an extension of Turkey's outlawed Kurdish rebels.
A U.S.-backed campaign is underway in Syria to take the city of Raqqa — the Islamic State group's de facto capital — from the militants. The fight is taking place under the banner of the predominantly Kurdish alliance known as the Syria Democratic Forces.
The Kurdish-led fighters have made small advances north of Raqqa since Sunday, taking over nearly a dozen villages, including the village of Laqtah , and another, small one on Tuesday.
The SDF enjoys the backing of several Western militaries and is recognized by the U.S. as the most effective force fighting against the extremists, but its differences with Turkey as well as other Syrian groups could complicate the campaign.
Warplanes from a U.S.-led coalition provided air cover for the advancing forces. The U.S. Central Command said on Tuesday that coalition aircraft conducted 15 airstrikes on Monday north of Raqqa, mostly near the area of Ein Issa, where the fighting appeared to be concentrated. On Sunday, the coalition carried out 16 airstrikes in same area.
Speaking in Ankara, Cavusoglu told reporters that he hoped the U.S. would keep its promise, but noted that Washington had also pledged earlier that Syrian Kurdish fighters would withdraw from the town of Manbij, which has not happened so far.
Cavusoglu said that during U.S. chairman of the Joint Chiefs of Staff Joe Dunfords' last visit to Turkey, the Americans said the Syrian Kurdish fighters "will only have a role in encircling Raqqa and will absolutely not enter the city."
"We hope that this will be the case and we expect that our partners keep their promises," he said.
There was no immediate comment from U.S. officials.
Speaking to the Kurdish news agency Hawar, SDF spokesman Talal Sillo said his forces will continue their campaign until Raqqa is liberated. He said the coalition has provided support, as well as new weapons, particularly anti-tank missiles.
"According to the agreements, there will be more support for the SDF until the campaign is completed and the city is freed from the mercenaries," he said, referring to IS militants.
Cavusoglu also said that Turkey prefers that "local" Arab forces enter the city, backed by U.S.-led coalition and possibly including Turkish ground troops.
"We still have weeks to the Raqqa operation," Cavusoglu said. "Our advice is for the local forces to be supported by our special forces."
The residents of Raqqa would not welcome Kurdish forces, the Turkish minister also suggested. If "terrorists enter into the city ... we should not force the people to choose between two evils."
The Raqqa-based Syrian activist group known as Raqqa is Being Slaughtered Silently said IS militants have prevented residents of a village that was bombed by the coalition forces from leaving, imposing a curfew there.
Both the Raqqa activist group and the Britain-based Syrian Observatory for Human Rights said that IS militants have blown up a number of bridges over irrigation canals north of Raqqa, near Ein Issa, where SDF are based, in an apparent attempt to curtail their forces' advances.