epa07255754 A general view at Manbij town in northern Syria, 31 December 2018. According to reports on 28 December 2018, The US-backed Kurdish People's Protection Units (YPG) and the Syrian Democratic Forces (SDF), which control a 250km territory in northern Syria, asked Assad's Syrian army to take over control of Manbij town (some 40 km from Syrian-Turkish border) in order to protect it from a potential Turkish attack. On 19 December 2018 US President Donald J. Trump announced the withdrawal of US forces from Syria, and on 24 December 2018 he said that Turkey, a NATO ally, will be clearing the last of IS pockets in Syria. Turkey classifies the YPG and SDF as terrorist organizations.  EPA/STR
The Manbij town site in northern Syria, 31 December 2018. 

Inside Manbij: Dispatch from the battle for Syria's future