The withdrawing convoy crossed the Tigris River at the Fishkhabur border post near the Turkish frontier, en route to Arbil, the capital of the autonomous Kurdistan Region, where there is a US base.

The United States announced the withdrawal of 1,000 American soldiers deployed in northeast Syria on October 13, the fifth day of Turkey's offensive against the Kurdish People's Protection Units (YPG), which Ankara considers a terrorist group.

On October 7, US soldiers withdrew from the Turkish border in northern Syria on orders of President Donald Trump, opening the way for Turkey's offensive against Kurdish forces.

The offensive was paused on Thursday by a fragile ceasefire negotiated by Washington.

On Sunday, an AFP correspondent saw more than a convoy of 70 armoured vehicles flying the American flag and escorted by helicopters drive past the Syrian town of Tal Tamr carrying military equipment.

The Syrian Observatory for Human Rights said the convoy was evacuating the military base of Sarrin, south of the border town of Kobane, and appeared to be heading east to Hasakeh province.

In the past week, US forces have withdrawn from three other bases in Syria, including from the key town of Manbij and another close to Kobane close to the Turkish border.

The United States currently has 5,200 troops posted in Iraq, deployed as part of a Washington-led coalition against the Islamic State group.

The US presence at several bases across Iraq is controversial, with numerous political groups and pro-Iran Shiite armed groups demanding their expulsion.