Syria’s deputy foreign minister Faisal Maqdad on Thursday attacked US-backed Kurdish led forces saying they had betrayed their country and accused them of a separatist agenda that gave Turkey a pretext to violate his country’s sovereignty.

Asked about whether Damascus should resume dialogue with the Kurdish-led forces that were facing a Turkish assault to oust them from northeast Syria, Maqdad said these “armed groups had betrayed their country and committed crimes against it.”

“We won’t accept any dialogue or talk with those who had become hostages to foreign forces … There won’t be any foothold for the agents of Washington on Syrian territory,” Maqdad told reporters in his office in Damascus.

A Syrian Kurdish official said earlier this week that the Kurdish-led authorities in northern Syria may open talks with Damascus and Russia to fill a security vacuum in the event of a full withdrawal of US forces from the Turkish border area.

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A top commander was also quoted as saying one option for the Kurds was to hand back territory to the Syrian government.

The powerful Kurdish YPG militia was helped by the Syrian government to take control of mainly Kurdish inhabited cities in the early days of the conflict, as Damascus turned its attention to quelling popular protests against President Bashar al Assad’s rule that turned later into an armed insurrection.

The Syrian Kurdish YPG never fought the government during the war, and even accommodated the Syrian government’s presence in its main city of Qamishli and has a lucrative illicit oil sales business with Damascus.

Damascus, however, is loathe to cede the Syrian Kurds the level of autonomy they seek. The government earlier this year threatened the US-backed Kurdish forces with military defeat if they did not agree to a return of state authority.