"We, members, soldiers, and officers of what was previously known as the Eighth Brigade, officially announce the dissolution of the movement and hand over all military and human capacities to the Ministry of Defense", it says in the statement from Colonel Mohamed al-Hourani.
The message comes after a few days of unrest between the group and the government in Damascus.
The Eighth Brigade is the most prominent in a coalition of armed groups in southern Syria, known as the Southern Operations Room (SOR).
Both the brigade and SOR are led by the same person, the defected army officer Ahmed al-Awdeh.
The coalition was founded at the beginning of December to participate in the overthrow of dictator Bashar al-Assad.
The uprising against al-Assad was led by the Islamist group Hayat Tahrir al-Sham, whose leader Ahmed al-Sharaa serves as Syria's interim president.
While several other rebel groups have agreed to dissolve and join the regular Syrian army, SOR has retained its weapons and presence in southern Syria, based in the city of Daraa.
