Syrian Democratic Forces Kurds
© Associated Press / Syrian Democratic Forces
The United States is concerned as Syrian Democratic Forces abandon their posts with the US-led coalition fighting Daesh* terrorist group to instead focus on operations in Syria's border district of Afrin, Department of State Spokesperson Heather Nauert said during a press briefing.

"We have seen as the situation in Afrin has taken hold that some of those SDF forces ... have started to leave their work with coalition partners, the fight against ISIS, and head over to Afrin to handle those types of issues," Nauert said on Thursday. "That takes the eye off the ball on ISIS. It's a concern of ours."

Nauert underscored that the SDF has been a tremendous and valuable fighting force in the fight against Daesh.

The SDF said in a statement on Tuesday that they had decided to send fighters to the Afrin region to help the Kurdish People's Protection Units (YPG) militia there fight the Turkish army.

On January 20, the Turkish Armed Forces launched an operation against Kurdish forces in Afrin, an area in northern Syria controlled by the US-backed YPG, which is considered by Ankara to be an affiliate of the Kurdistan Workers' Party (PKK), designated as a terrorist organization in Turkey and several other countries. Damascus has strongly condemned Ankara's actions, with the Syrian Foreign Ministry calling them a violation of the country's sovereignty.