The Syrian Democratic Forces (SDF) dissolved on Tuesday after their commander announced the completion of their integration into the Syrian army, ending the existence of the Kurdish-led force that served as Washington's main partner against the so-called Islamic State group in Syria and once controlled a vast autonomous zone in the country's northeast.

"We announce today the end of the mission of the Syrian Democratic Forces and declare, with full responsibility, their dissolution as an independent military force," Mazloum Abdi said in a televised speech at the presidential palace in Damascus, following meetings with President Ahmad al-Sharaa.

The SDF was formed in 2015 at US instigation to fight the IS group, drawing primarily on the People's Protection Units, known by its Kurdish initials YPG, the main armed force of Syria's Kurdish community.

At its peak, the SDF controlled a de facto autonomous zone across much of northeastern Syria, including significant oil and agricultural land.

Turkey regards the YPG as the Syrian branch of the Kurdistan Workers' Party, or PKK — designated a terrorist organisation by Turkey, the US, the EU, the UK and France — and has conducted multiple military operations against it inside Syria.