Members of Syrian rebel groups allied with Turkey are seen in the Turkish border town of Ceylanpinar, on their way to northern Syrian town of Ras al-Ayn, on Oct. 23, 2019. Turkish Defense Ministry said on Wednesday that there is no need for new operation outside the present operation area, as the United States has confirmed that the withdrawal of the Kurdish People's Protection Units (YPG) has completed. Photo:Xinhua

Kurdish forces in northeastern Syria left several positions along the long border with Turkey on Thursday, complying with a deal that sees Damascus, Ankara and Moscow carve up their now-defunct autonomous region.

Russian forces have started patrols along the flashpoint border, filling the vacuum left by a US troop withdrawal that effectively handed back a third of the country to the Moscow-backed regime of President Bashar al-Assad.

US President Donald Trump has praised the agreement reached in Sochi by Turkey and Russia and rejoiced that US personnel were leaving the "long blood-stained sand" of Syria, leaving just a residual contingent behind "where they have the oil."

The deal signed in the Black Sea resort by Syria's two main foreign brokers gives Kurdish forces until Tuesday to withdraw to a line 30 kilometers from the border.

The Syrian Observatory for Human Rights reported that the Kurdish-led Syrian Democratic Forces (SDF) had pulled out of some areas at the eastern end of the ­border on Thursday.

Fighters of the Kurdish People's Protection Units (YPG) - the main component of the SDF - remained in many positions along the 440-kilometer border, he added.

The Observatory also reported clashes near the town of Tal Tamr between SDF fighters and some of the Syrian former rebels paid by Turkey to fight ground battles.

Russian and Syrian government forces were deploying across the Kurdish heartland where they are tasked with assisting "the removal of YPG elements and their weapons."

Kurdish forces had already vacated a 120-kilometer segment of the border strip - an Arab-majority area between the towns of Ras al-Ain and Tal Abyad.

The SDF withdrawal from that area came after Turkey and its Syrian proxies launched their deadly cross-border offensive on October 9.

Turkish President Recep Tayyip Erdogan, who is embattled on the domestic political front, hopes to use the pocket to resettle at least half of the 3.6 million Syrian refugees his country hosts.

Under the Sochi deal, the area will remain under the full control of Turkey, unlike the rest of the projected buffer zone which will eventually be jointly patrolled by Turkey and Russia.