More than 400 US Marines are to leave Syria after helping to capture the city of Raqqa from so-called Islamic State.
Marine units have been deployed since March to provide artillery support to an alliance of Syrian Kurdish and Arab fighters battling the jihadist group.
The Syrian Democratic Forces (SDF) declared victory in Raqqa last month.
The US-led coalition against IS said the withdrawal of the Marine artillery battery was a “sign of real progress”.
“We’re drawing down combat forces where it makes sense, but still continuing our efforts to help Syrian and Iraqi partners maintain security,” Brig-Gen Jonathan Braga, the director of operations for the coalition, said in a statement.