The Syrian Democratic Forces (SDF) is a Kurdish-led coalition formed by ethnic militias and rebel groups, and serves as the official military wing of the Autonomous Administration of North and East Syria (AANES). The SDF is allied to and supplied by the United States–led CJTF–OIR international alliance. Founded in 10 October 2015, the SDF claims that its mission is fighting to create a secular, democratic and federalised Syria. The SDF is opposed by Turkey, who claims the group has direct links to the PKK, which it recognizes as a terrorist group.

The Syrian opposition is the political structure represented by the Syrian National Coalition and associated Syrian anti-Assad groups with certain territorial control as an alternative Syrian government.