United Nations- The United Nations has invited Morocco and the Algerian-backed Polisario Front to talks in December on ending their decades-old conflict over Western Sahara, diplomats said Saturday.

UN envoy Horst Koehler, a former president of Germany and ex-director of the International Monetary Fund, has invited the two sides along with Algeria and Mauritania to Geneva for talks on December 4-5.

In letters sent to the four parties, the envoy requested a response by October 20, according to diplomatic sources.

Morocco has said that negotiations on a settlement should focus on its proposal for autonomy for Western Sahara and rejects the Polisario’s insistence on an independence referendum.

The Polisario Front fought for control of the Moroccan territory of Western Sahara from 1975 to 1991.

Diplomatic efforts to end the conflict have been deadlocked since the last round of UN-sponsored talks in 2008.