The Kurdish-led Syrian Democratic Forces (SDF) and the Syrian Democratic Council (SDC) have agreed to integrate their military forces into the army of the new Syrian government.
The agreement is also believed to involve the Autonomous Administration of North and East Syria, commonly known as "Rojava", which is the civil authority that rules SDF-held areas of Syria.
The fighters are believed to be those affiliated with the Kurdistan Workers Party (PKK), which waged a decades-long insurgency against key Syrian ally Turkey, and which has many forces in neighbouring Iraqi Kurdistan.
The Syrian Democratic Union (PYD), which is the main component force of the SDF, is essentially the Syrian wing of the PKK, meaning that this move will bring an end to fighting between the SDF and Turkish-backed forces that have blighted post-Assad Syria.
The SDF held around 25 percent of Syrian territory, including many of the richest areas in terms of oil, natural gas and minerals, with many of these areas being Arab-majority areas prior to the war and their conquest by the Kurdish force.
There has not yet been any comment from the US, which materially and physically supports the SDF, including the use of several American bases in the areas under their control.