The military moves last year were one of the most tense in recent years between Morocco and Polisario, which declared an independent republic in the disputed desert land in the 1970s and fought a guerrilla war with Morocco until a 1991 ceasefire.
The standoff in Guerguerat began last year when U.N. troops stepped in after Moroccan gendarmerie crossed beyond Moroccan-controlled areas in what they said was a road clearing operation, prompting the mobilization of Polisario forces.
The Moroccan Foreign Ministry said in a statement on Sunday, that King Mohammed had ordered "a unilateral withdrawal from the zone" in conformation with the U.N. Secretary General's recommendations.
Polisario forces were not immediately available for a response.
The spokesman for the U.N. Secretary General had released a statement on Saturday calling on all parties to "unconditionally withdraw all armed elements from the Buffer Strip as soon as possible".
Polisario accused Rabat of breaking the terms of the ceasefire last year by trying to build a road in the U.N. buffer zone. Morocco says it was just a clearing operation that broke no terms of the ceasefire.
U.N. peacekeepers had been stationed between Moroccan forces and a brigade of Polisario troops who were just 200 meters apart in an area between a Moroccan-built earth wall marking Moroccan controlled territory and the Mauritania frontier.
(Reporting by Samia Errazzouki; editing by Patrick Markey)