UN Secretary-General Antonio Guterres on Tuesday urged all parties meeting in Geneva this week to discuss the Western Sahara dispute to be constructive and impose no conditions for formal talks.
Morocco, the Polisario Front, Algeria and Mauritania are taking part in two days of roundtable discussion with a UN envoy starting on Wednesday to try to relaunch negotiations, which have been stalled since 2012.
Guterres "urges all to engage in good faith, without preconditions and in a constructive spirit in the discussions," said a statement from his spokesperson.
The UN chief expressed support for the UN envoy, former German president Horst Koehler, who is seeking to revive negotiations.
The United Nations has repeatedly failed to broker a settlement in Western Sahara, where Morocco and the Algerian-backed Polisario fought for control from 1975 to 1991.
A UN peacekeeping mission has been deployed in the contested territory since 1991 to monitor a ceasefire and organize a referendum on the status of Western Sahara, which never materialized.
Morocco insists that any negotiation on the territory should focus on its proposal for autonomy while the Polisario maintains that the status of Western Sahara should be decided in a referendum on independence.
The United States has led a push at the UN Security Council to revive talks and has suggested that the UN mission there, MINURSO, will not remain if the parties are unwilling to seek a settlement.
The Security Council must decide on renewing the MINURSO mission before April 30.