The U.S. currently has hundreds of troops deployed in eastern Syria as part of a coalition fighting the Islamic State group.
The U.S. handed over its last military bases in Niger to local authorities last month, but about two dozen American soldiers had remained in Niger.
Once an emblem of the two countries' security ties, Air Base 201 will be vacated by Monday, according to two U.S. officials.
The U.S. military commander in Niger says all American forces and equipment will leave a small base in the West African country this weekend.
