When Spain relinquished control of Western Sahara in 1975, the United Nations had already recognized it as a non-self-governing territory entitled to the guarantees provided by the UN Charter, including the right to self-determination.
However, in November of that year King Hassan II of Morocco moved to fill the vacuum left by Spain. A "green march" of tens of thousands of Moroccans crossed the border into Western Sahara to stake Moroccan sovereignty. This led to a prolonged conflict with the pro-independence Polisario Front. In 1991, the two parties agreed to a cease-fire to be followed by a referendum. The subsequent deadlock has been due to Morocco's refusal to allow any referendum that may lead to Western Sahara's independence.
To this date, most of Western Sahara is controlled by Morocco. Some 250,000 Saharawi refugees lead a miserable life in the Algerian desert. A 1,700-kilometer wall separates 130,000 Moroccan troops from Polisario forces that have nominal control over a swath of land bordering Algeria and Mauritania. UN military observers monitor the 1991 cease-fire.
Through the years, Morocco has strengthened its hold over Western Sahara. Moroccan settlers now constitute the majority of the population. The natural resources of the territory, which under the UN Charter should be used for the sole benefit of the Saharawi people, are being exploited by Morocco.