Morocco has accused the Algerian-backed Polisario Front of carrying out incursions in the buffer zone near Guerguerat, an area in southern Western Sahara near the Mauritanian border.
The UN chief “is deeply concerned about recent increased tensions in the vicinity of Guerguerat in the Buffer Strip in southern Western Sahara between the Moroccan berm and the Mauritanian border,” said a UN statement.
Guterres “calls on the parties to exercise maximum restraint and to avoid escalating tensions.”
“Regular civilian and commercial traffic should not be obstructed and no action should be taken, which may constitute a change to the status quo of the buffer strip,” it added.
A previous incursion of the Polisario at Guerguerat last year prompted the United Nations to intervene to force both Morocco and the Polisario to withdraw.
The spike in tensions come as new UN envoy Horst Kohler is working to restart talks between Morocco and the Polisario on ending the decades-old conflict.
Morocco and the Polisario fought for control of Western Sahara from 1974 to 1991, with Rabat taking over the desert territory before a UN-brokered ceasefire in the former Spanish colony.
Rabat considers Western Sahara an integral part of Morocco and proposes autonomy for the resource-rich territory, but the Polisario Front insists on a UN referendum on independence.