International armed conflict between Morocco and Western Sahara

Historical Background

Context and status

Western Sahara is a non-self-governing territory on the Atlantic coast of north-west Africa, bordering Morocco, Algeria, and Mauritania. It was colonized by Spain from the late nineteenth century and listed by the United Nations (UN) as a non-self-governing territory in 1963, placing it within the decolonization framework and the right of peoples to self-determination.

Competing claims and early process

Morocco and Mauritania asserted sovereign rights, while the Polisario Front formed in 1973 to oppose foreign control and pursue independence. In 1975, the International Court of Justice (ICJ) found Western Sahara was inhabited at the time of colonization and that historical legal ties did not amount to territorial sovereignty for Morocco or Mauritania. The same year, a visiting UN mission reported Sahrawi support for Polisario and for independence.

Occupation, armed resistance and ceasefire

After the 1975 ‘Green March’, during which hundreds of thousands of Moroccan volunteers, responding to King Hassan II’s call, marched toward and into Western Sahara, Spain decided to withdraw from the country. Shortly thereafter, the ‘Madrid Accords’, signed by Mauritania, Morocco, and Spain, established a temporary administration of the territory by Morocco, Mauritania, and Sahrawi representatives, the ‘Yema’a’ or ‘Jemaâ’. Morocco and Mauritania then occupied the territory, prompting armed resistance from Polisario Front. In 1979, Mauritania withdrew, and Morocco subsequently extended control over most of Western Sahara and built the Berm (system of sand barriers designed to prevent enemy incursions). In 1991, a ceasefire brokered by the UN envisaged a referendum and created the UN Mission for the Referendum on Western Sahara (MINURSO), but the vote stalled amid disputes between Morocco and Polisario Front over the identification of voters, the appeals process, and the repatriation of refugees.

Diplomatic initiatives and renewed hostilities

UN-led initiatives, including the 2003 Baker proposal, failed, and subsequent talks did not resolve the core issues between the parties. In June 2015, the Polisario Front, as the representative of the Sahrawi people, deposited a unilateral declaration based on Article 96(3) of Additional Protocol I, calling for the application of the Protocol and the Geneva Conventions. The existence of an international armed conflict with Morocco was accepted by the Swiss Federal Council. In October 2020, pro-Polisario protesters blocked the Guerguerat crossing in the UN-administered buffer zone, and the following month Morocco conducted a military operation to reopen it, prompting the Polisario Front to declare the ceasefire ended. In the months that followed, hostilities between the two parties persisted, alongside Moroccan resort to armed drones. In parallel, diplomatic alignments further diverged, with several States voicing increased support for Morocco’s autonomy plan, while other States maintained or reaffirmed support for Sahrawi self-determination and criticized Morocco’s claim and continued presence.

Key Developments (2023–2025)

1. Ongoing Hostilities: Low-intensity hostilities persisted during the reporting period. Incidents include Moroccan strikes in Polisario-held areas and repeated Polisario attacks into Moroccan-controlled Western Sahara, including in areas near MINURSO sites, with disputed casualty claims. Morocco deployed artillery and established positions within the UN buffer zone, while drone strikes became increasingly frequent.

2. UN’s Political Process: The UN envoy for Western Sahara pursued renewed consultations from 2023 onward through visits and meetings with Morocco and the Polisario Front, as well as Algeria and Mauritania, without changing the parties’ core positions. In 2024, the envoy floated a number of options including partition, which was rejected by both sides, and MINURSO’s mandate was renewed. In 2025, consultations continued and the Security Council backed Morocco’s autonomy plan as a basis for a political solution while recalling the right of Sahrawi people to self-determination. The Moroccan Autonomy Plan, primarily supported by the United States, gained increasing support from other States.

3. Regional and Internal Developments: In October 2024, following the expiry of a fishing agreement between the European Union (EU) and Morocco, EU judicial rulings reiterated Western Sahara’s separate and distinct status from Morocco, prompting efforts to renegotiate arrangement with Morocco. Relations between Morocco and Algeria were increasingly acrimonious amid Algeria’s support to the Polisario Front. Within the Front, leadership disputes, defections, and divisions over engagement with UN processes were reported.