On 5 August 1979, after years of clashes, the Sahrawi Arab Democratic Republic (SADR) and Mauritania signed a peace agreement and Moroccan troops became the only force against the POLISARIO Front, intensifying attacks in Sahrawi territory and Morocco.

The deployment of the FAR (Royal Moroccan Armed Forces) to a more extensive territory benefited the Polisario Front, which attacked key points with more ferocity and began to tip the balance of the conflict towards the Sahrawi side. This altered the security of Morocco and its population and prompted the construction of 2700 km of border walls between 1980 and 1987. Click here for more information. (in Spanish)

In 1988, a high-level Sahrawi delegation met with Hassan II in Marrakech with the support of the United Nations (UN) and the African Union (AU). At this meeting, both parties agreed to accept a peace plan which would culminate in the holding of a referendum of self-determination in Western Sahara (Resolution 621, 1988). To ensure the success of this plan, a group of observers would monitor the cease-fire while the UN would supervise the organisation of the referendum, which would be based on the 1974 Spanish census in Western Sahara.

On 17 June 1990, Resolution 658 (a Settlement Plan approved by the Security council) was passed. Months later, in April 1991, the MINURSO (United Nations Mission for the Referendum in Western Sahara) was created to monitor the cease-fire agreements and to carry out the program of identification and registration of legitimate voters for the referendum.

Finally, the cease-fire was officially signed on 6 September 1991 (the day after MINURSO was established in El Aaiún).

On 30 December 1999, MINURSO concluded the identification process. At its conclusion, and in view of the possibility that the option of independence for Western Sahara might win, Morocco withdrew from the peace plan. Just the following year, the Security Council resolutions began to speak of a "mutually acceptable" solution (Report of Secretary-General 17/02/2000).

After several failed plans, such as the Baker Plan II (a plan that would've benefitted the occupier but was accepted by the Polisario Front). In 2007, Morocco presented a proposal for autonomy which was answered by a proposal for self-determination by the Polisario Front.

During the almost 30 years of the Settlement Plan that sponsored the cease-fire, Morocco has systematically refused to accept any plan that would give the slightest possibility of independence for Western Sahara. The Polisario Front, for its part, has refused to accept anything which would deny the option of self-determination. Following the resignation of 5 special envoys who, in many cases, have denounced Moroccan obstructionism, Steffan de Mistura, an Italian-Swedish diplomat, has taken over this role, aiming to reach an agreement between the parties.