Kurdish forces will likely participate in the liberation of Daesh's de facto Syrian capital "in one form or fashion", the general in charge of the U.S.-led coalition said Wednesday.
Speaking to reporters via video link from Baghdad, Iraq, Gen. Stephen Townsend said "Kurds will participate in the operation."
"The facts are there are Kurds from Raqqa, and larger Raqqa district and province," he said.
"I don't think we're going to change the demographics of Raqqah by Kurds or Turkomen or any group participating in the operation. But I expect that probably all types of Syrians in northern Syria will participate in the liberation of Raqqah," he added.
Turkish President Recep Tayyip Erdogan has said that Turkey-backed Free Syrian Army fighters could lead the Raqqah offensive.
Turkey views the YPG as the Syrian offshoot of the outlawed PKK group. Turkey, the U.S., and EU have designated the PKK as a terror group, and it resumed its decades-old armed campaign in July 2015.
Washington has refrained from similarly labeling the YPG, and has relied on the group as its principal on the ground partner in Syria to Ankara's consternation.
Seeking to allay Turkish concerns about the YPG, Townsend said he's been assured by the group's leaders that "they have no desire to attack Turkey."
"They desire to have a good working relationship with Turkey and I have seen absolutely zero evidence that they have been a threat to or supported any attacks on Turkey from northern Syria over the last two years," he said.
The YPG forms the backbone of the U.S.-backed Syrian Democratic Forces (SDF) in northern Syria where the SDF has ousted Deash from successive towns and villages with coalition air support, training and advisors.
Townsend said he believes the SDF will lead the Raqqah operation, but stressed that no final decision has been made.
If the SDF is to lead to lead the charge, Townsend said they "will probably need additional combat power".
"But those decisions have yet to be taken," he said.
Responding to claims that pictures posted by U.S. Central Command (Centcom) depict child soldiers in the ranks of the SDF, Townsend maintained that the coalition does not "allow child fighters, underage fighters".
And as the general was speaking to reporters, Centcom wrote on Twitter that "All partner nation trainees are vetted through an interview process, including age."
"Those not willing to provide assurances to this vetting process are disqualified," the Middle East command added.
Townsend confirmed that Russian and Syrian airstrikes hit Arab components of the SDF on Tuesday outside of al-Bab, the city Turkish-backed forces recently liberated from Daesh in northern Syria.
The aircraft thought the areas "were held by ISIS", but Syrian Arab fighters that are part of the SDF had recently moved into the targeted villages that were recently vacated by Daesh, Townsend said.
The American general did not detail casualties beyond confirming that some had occurred before the air raids were halted through a U.S.-Russian channel meant to prevent accidental clashes.
U.S. forces were about five kilometers away, Townsend said.
