The US on Sunday withdrew its forces from military observation post south of Ayn Al-Arab in northern Syria, according to security sources. 

The US started to withdraw from Ayn Al-Arab, also known as Kobani, at 15:00 p.m. local time [1200GMT].

Earlier, US Secretary of Defense Mark Esper said that the U.S. is preparing to evacuate about 1,000 U.S. troops from northern Syria.

The decision came a week after US President Donald Trump announced that the US would pull back its forces from the Syrian border after a telephone call with Turkish President Recep Tayyip Erdogan.

Turkey on Wednesday launched Operation Peace Spring east of the Euphrates River in northern Syria to secure its borders by eliminating terrorist elements and to ensure the safe return of Syrian refugees and Syria’s territorial integrity.

On Saturday, Turkey's defense minister said that targeting the U.S. observation point in Syria was out of question during the ongoing counter-terror operation.

Ankara wants to eliminate terrorist elements of the PKK and its Syrian offshoot, the PYD/YPG, from the region.

In its more than 30-year terror campaign against Turkey, the PKK -- listed as a terrorist organization by Turkey, the US and the European Union -- has been responsible for the deaths of 40,000 people, including women, children, and infants.