Ash Carter’s comments came during a Senate Armed Services committee meeting where lawmakers asked him whether Russia could negotiate a federal structure for the PYD in Syria as Bashar al-Assad’s government is not resistant to a declaration of a federal state in the north of the country made Thursday by the Kurdish group.

“We and others in the region including the Turks will have a major role in Geneva in deciding about the manner of participation of the Kurds. So Russia has an important role in this. We have an important role to play as well” Carter told lawmakers noting that he does not think Russia can bring the PYD’s aspirations to the negotiation table.

The defense chief’s comments followed those of State Department spokesman Mark Toner on Wednesday who said the U.S. would not support any autonomy in the war-torn country amid ongoing peace talks.

But a State Department spokesperson said the U.S. position for a unified Syria would remain until the Syrians “get to a point where they feel they have got something" after the talks.

"Then we can have a conversation about what it [structure and governance of Syria] looks like" he said.

Carter at the same time noted the PYD’s cooperation with the U.S. against Daesh describing the group as an “excellent partner” on the ground in the fight.

“We are grateful for that. We intend to do that recognizing complexities of their role in the region” he added.

The U.S. has provided air cover to the PYD and supported others fighting along with the group under the umbrella of the Syrian Democratic Forces an alliance recently introduced by PYD. Turkey as a partner in the U.S.-led coalition countering Daesh and NATO ally has been pressing the U.S. to stop supporting the group for its separatist aspirations and link with the PKK terrorist organization.

The State Departmentsaid although the U.S. would not recognize self rule by the PYD in Syria it would continue to provide arms to the group.

Speaking to Russia’s withdrawal from Syria Carter told lawmakers that he said from the very beginning when the Russians intervened in Syria in late September that it was a “wrongheaded” move.

Noting that the U.S. is watching them withdraw Carter said that he does not know how far it would go.

“They said they would fight ISIS and they didn’t. Instead they supported Assad which prolonged the civil war fueled the civil war” he said. “Their effect has been the opposite of what they have stated.”

He suggested that now “Russia can do what it should do” – use its influence over the Assad government to promote a transition in the country. Carter also told 6the Senate panel that Daesh extremism cannot be “tolerated in a generational way” as it continues to spread threats not only to the region but also to the Western world. Thus he said the U.S. is investing in accelerating the campaign against the militant group.

“But that is not going to automatically create a Middle East free of extremism and it is not going to create a world free of terrorism because the trends and technology has put more and more destructive power in the hands of smaller and smaller groups.”

“We are willing to lead this [war against extremism] we are willing to do a lot because we are the most powerful but we need others to get in the game” he said. “We are gonna defeat ISIL and will remember who played their role and who didn’t."