Moroccan political parties leaders on Thursday made it clear that Morocco's sovereignty over its Southern provinces, the Sahara, is not negotiable, stressing however the North African country's commitment to pursue peace talks with the Polisario in a bid to end the 32-year old dispute over the former Spanish colony.

The Secretary-General's Personal Envoy for the Sahara, Peter Van Walsum, starts a visit to the region from February 6 to February 14, UN spokesman, Michèle Montas said, on Monday.

 UN Secretary General, Ban Ki-moon said participants in the third round of Manhasset negotiations on the Sahara (January 7-9) concurred on the need for "a more intensive and substantive phase of negotiations."

Deputy chairman of the European Parliament budget committee, Ralf Walter, called on the European Commission (EC) to publish the investigation report of the European Anti-Fraud Office (OLAF) on Polisario's embezzlement of humanitarian aid in Tindouf camps, southwest Algeria.

Morocco proved good will during the recent negotiations on the Sahara dispute with Algerian-backed separatist movement "Polisario" in Manhasset (outskirts of New York), unlike the "negative, fixed, and sterile attitude of the other party," minister of Communication and Government spokesperson, Khalid Naciri, said on Thursday.