SDF (Syria's Democratic Forces) has established its own self-governance in the northeast, called Rojava. The US has provided them with military support in battles against the jihadist movement IS, and nearly 1,000 American soldiers are stationed there.
In recent turmoil, the Kurdish-led forces have been attacked by Turkey-backed rebels and pressured by forces led by the Islamist movement Hayat Tahrir al-Sham (HTS), which is taking over power in Syria.
"Believe it will continue"
We have worked side by side with SDF for a long time, and that work will continue, says the US's outgoing Defense Minister Lloyd Austin, according to American media such as CNN.
We have a good relationship with them, and I believe it will continue.
In the north, the Kurds have long been threatened by Turkey, which has established a "security zone" along the border with Kurdish-controlled areas in Syria using military force. The country has also enabled an Islamist rebel rule based in Idlib in the northwest.
Turkey's government labels SDF as a terrorist organization, based on the fact that a large part of the forces come from the PKK's armed wing YPG (People's Defense Forces).
Priority: Stop IS
In practice, this has meant that Turkey has clashed with many of its NATO allies, as they backed SDF in a US-led coalition and armed the group to fight against IS.
When the US withdrew most of its forces from Syria in 2019, the Kurds made a compromise with dictator Bashar al-Assad's regime, allowing government forces to take over areas as a buffer zone against Turkish or Turkey-backed attacks.
The US Defense Minister Austin now says that the US's top priority is to keep American forces safe and to "prevent IS from growing again".
Hundreds killed
On Tuesday, SDF announced that they had reached an agreement with American mediation to withdraw from the border city of Manbij in the north.
Over the past few days, more than 200 people have been killed in battles between Turkey-backed rebels and Kurdish-led forces in the north, according to reports from the Syrian Human Rights Observatory.
Further south, in eastern Syria, HTS-led forces claim to have taken control of the city of Dayr az-Zawr, which was under SDF's control. SDF says it has only made a minor retreat there.
