The UN chief has urged the global community to ensure tensions do not erupt again in the Guergerat area in Western Sahara.
The territory is located on the north-west coast of Africa and is bordered by Morocco, Mauritania and Algeria.
For 16 years, the Frente Polisario independence movement fought Morocco for control of Western Sahara before signing a ceasefire in 1991.
Jocelyne Sambira reports.
In a statement issued on Friday by his Spokesperson, UN chief Antonio Guterres praised Frente Polisario for removing its elements from Guergerat, a strip of land that serves as a neutral area in Western Sahara.
Unarmed military observers deployed to the area by the UN Mission in the country, MINURSO, confirmed the withdrawal was carried out in the past two days.
The buffer strip lies between the Moroccan berm, a defensive sand wall, and the Mauritanian border.
Morocco had already withdrawn its elements from the area in response to the urging of Mr Guterres.
Meanwhile, the Security Council has voted unanimously to extend the mandate of the UN Mission for another year.
MINURSO is responsible for monitoring a ceasefire between Morocco and the Frente Polisario and organizing, if the parties agree, a referendum on self-determination in Western Sahara.
Source: United Nations Radio