The Kurdish-led Syrian Democratic Forces have resumed operations alongside the global coalition fighting Islamic State, a sign that ties between the U.S. and the Kurds are mending after Turkey sent forces across the border to establish a safe zone in northeastern Syria.

The SDF is “resuming its joint program of work” to combat Islamic State and to secure infrastructure in northeastern Syria, Kurdish Gen. Mazloum Abdi said on Wednesday on Twitter. The work will depend on the “current stage and new developments on the ground,” he said.

President Donald Trump was widely criticized last month for giving the green light to Turkey to launch its military operation against the Kurdish fighters. The decision was criticized by both Republicans and Democrats in the U.S. Congress, where Trump’s move was regarded as the betrayal of a loyal ally and bulwark against Islamic State.

Mazloum warned after Turkey’s move that the SDF wouldn’t be able to fight Islamic State and Turkey at the same time and that his fighters would be forced to abandon prisons they’ve been guarding that hold Islamic State prisoners.

Separately, James Jeffrey, the U.S. envoy for Syria engagement and the special envoy to the coalition to defeat Islamic State, will meet senior Turkish leaders and members of the Syrian opposition in Ankara and Istanbul from Nov. 8-9, the State Department said on Wednesday.

Jeffrey is expected to discuss the current situation in northeast Syria as well as “our continued efforts to ensure an enduring defeat” of Islamic State, the State Department said.