Washington–U.S. Secretary of Defense Ashton Carter and his British counterpart Michael Fallon announced on Wednesday that the battle to liberate the ISIS-held Syrian city of Raqqa would be launched in the coming weeks.

Carter, who arrived in Brussels on Wednesday to attend the meeting of NATO Ministers of Defense, said in an interview with NBC news channel that the operation to regain Raqqa was planned to follow the beginning of the assault on Mosul in Iraq.

In Washington, Pentagon officials said that preparations were underway to launch a decisive military battle against ISIS in Raqqa.

Lt. Gen. Stephen Townsend, the top American military commander in Iraq, said it was imperative that operations to isolate the city begin soon to prevent attacks on the West that could be launched or planned from the militants’ capital.

“We think there’s an imperative to get isolation in place around Raqqa because our intelligence feeds tell us that there is significant external operations attacks planning going on, emanating central in — centralized in Raqqa,” Townsend said.

Townsend stressed that Kurdish militia fighters would be a part of the ground force used to isolate Raqqa.

“We’re going to go with who can go, who’s willing to go soon,” General Townsend told reporters at the Pentagon during a video news briefing from Baghdad. “And then, once we get the initial isolation in position, we’ll look at how we prosecute the operation further”, he added.

Townsend said talks are underway with Turkey about its possible role in the Raqqa operation and particularly about what role Syrian Kurds will play in Raqqa.

He noted, however, that the battle for Raqqa will take longer than the current battle for Mosul given that the anti-ISIS partners in Syria do not have the resourcing available to the Iraqi military.

He added that the 300 American military advisers in Syria will also have a light footprint as part of a Raqqa operation.