The United Nations peacekeeping mission in Western Sahara ceased operations on Sunday after 35 years, following a deadlock in the Security Council that left the force without a renewed mandate.

The mission, known as MINURSO — the Mission for the Referendum in Western Sahara — was established in 1991 to monitor a ceasefire and prepare a referendum on the territory's future. That vote never took place.

"This 1 November 2026 marks the start of the liquidation period," said Stephane Dujarric, spokesperson for the UN secretary-general. "A smaller team reporting to the United Nations' Department of Operational Support will oversee the orderly transportation of assets belonging to troop-contributing countries to their respective nations, and the appropriate disposal of equipment belonging to the United Nations."

The collapse of the mission followed a sharp confrontation in the Security Council on Friday. The United States proposed a resolution that would have extended the mission for one year, removed the word "referendum" from its name, and made Morocco's autonomy proposal the sole basis for further negotiations. Russia vetoed the draft, despite support from 11 of the 15 council members, including permanent members France and the United Kingdom. A competing Russian resolution to extend the mission was then voted down, leaving MINURSO without a mandate.

UN Secretary-General Antonio Guterres confirmed the mission's end and warned of potential instability. He said he "remains concerned about the security situation throughout the territory and the risk of escalation of hostilities," urging all parties "to exercise maximum restraint and to refrain from actions that could further increase tensions or undermine regional stability."

Guterres also said the UN "stands ready to continue supporting efforts to advance dialogue and pursue a peaceful resolution of the conflict," and called upon all parties to respect and promote the rights of the people of Western Sahara.

Western Sahara is a vast desert territory along Africa's northwestern Atlantic coast, roughly the size of Colorado, according to one source, or Britain, according to another. Rich in minerals and fisheries, it is classified by the UN as a "non-self-governing territory." Critics of Morocco's control describe it as Africa's last colony.

Once ruled by Spain, the territory has been at the centre of Africa's longest-running territorial dispute. Morocco annexed it in 1975 following Spain's withdrawal. An armed conflict that followed lasted more than 15 years and claimed more than 16,000 lives on both sides, according to the French Senate. A UN-brokered ceasefire took effect in 1991.

Morocco administers nearly all of the disputed territory, except for a narrow strip east of a Moroccan-built sand wall, known as the "free zone." Bringing Western Sahara under full sovereignty has been a central objective of Moroccan foreign policy for decades. Rabat refers to the territory as its southern provinces and has secured the backing of a growing number of Western capitals, including Washington, Paris and London.

The Polisario Front, backed primarily by Algeria, seeks independence for the territory, which it considers the homeland of the Indigenous Sahrawi people. Operating from refugee camps near the Algerian city of Tindouf, the movement aims to establish an independent Sahrawi Republic. Its international support has dwindled in recent years.

The referendum envisioned in 1991 never materialised. Morocco wanted the voter list to include Sahrawis living in the territory it controls, while the Polisario objected, arguing that their inclusion would tilt the outcome toward integration with Morocco. The movement insisted on using Spain's colonial census to determine voter eligibility.

Morocco's royal palace welcomed the non-renewal of the mission, calling it a "significant development" in withdrawing the Western Sahara issue from the Security Council's consideration. It had previously described the mission as "an instrument to internationalize the dispute."

Algeria's Foreign Ministry expressed "deep regret" over the non-renewal, criticising what it called the "excessive bias" of the US draft resolution toward Morocco's position. The Polisario Front called the decision "unacceptable" and said it was "concerned at the deadlock in the Security Council meeting."

Speaking after Friday's vote, US Ambassador to the UN Mike Waltz said it was "truly unfortunate" that the veto had been used to preserve the word "referendum" in the mission's name, adding that Washington's proposal "would have moved the 50-year conflict forward" and that the status quo is unacceptable.

Russia's UN Ambassador Vassily Nebenzia said Moscow opposed the US draft because it favoured one side. "We stress the fact that the Security Council cannot automatically predetermine matters relating to sovereignty," he said.

MINURSO was authorised to have 534 personnel. Its 2026–2027 budget exceeded 62 million dollars. Twenty mission personnel lost their lives during its 35-year operation. The top military contributors to the force were Egypt, Ghana and Pakistan.