I was Kofi Annan's envoy to Africa's last colony. Why I resigned in protest … and why I've decided to speak out.

“Come stai…? Tutto bene…?” This had been U.N. Secretary General Kofi Annan's opening line since the early days of our professional relationship. I'd heard him use the greeting many times as he rose through the ranks, resorting to it whenever he met an Italian colleague (like me). Still, those words never failed to warm my heart. Walking around his desk Kofi smiled, hand stretched out towards the black leather sofa. It was early September 2006. Both Annan and I were about to leave the United Nations for good. He was leaving after two terms in office. I had just resigned, in protest, from my post as his special representative in Western Sahara. Dashing any remaining hopes, our last conversation turned out to be emblematic of the blandness and ambiguities that characterize U.N. engagement with Africa's last colony. Since then, I have witnessed the organization and its leaders continuing to perpetuate a grave injustice in Western Sahara, contrary to their own promises and obligations.

Half the size of France, Western Sahara lies on the Atlantic coast of Africa between Morocco and Mauritania. A desert land, it has been inhabited since time immemorial by Arab-Berber nomadic tribes. Since the mid-'60s, the United Nations has issued a staggering number of resolutions supporting the Saharawis' inalienable right to self-determination under the U.N. Charter. Yet, when Spain withdrew from what was then Spanish Sahara in 1976, it failed to organize a referendum so that its inhabitants could choose their future status. And the territory was soon swallowed up by a new colonizer: King Hassan II of Morocco.

In invading Western Sahara, the King was pursuing an old vision of greater Morocco and seeking access to natural resources. He launched a "Green March" of some 350,000 Moroccans who crossed the border unopposed by the Spanish army. The subsequent military operation was brutal. Under bombings by the Moroccan air force, tens of thousands of Saharawis began to flee the few urban areas for the desert inland. Morocco started a program of settlements not dissimilar from that carried out by Israel in Gaza and the West Bank after the Six-Day War. A bloody desert war ensued between the occupier and the pro-independence POLISARIO front. It was not until 1991 that the two sides agreed on a ceasefire to be followed within nine months by a referendum for self-determination, facilitated by the United Nations. However, because of Moroccan resistance supported by powerful allies like France and the United States, that referendum never took place.

The price of inaction has been high. Morocco has constructed a wall 1,400 miles long, cutting the entire territory of Western Sahara in half. An amazing sight, the berm separates the territory under Moroccan control, on the Atlantic coast, from an area bordering Mauritania and Algeria, where POLISARIO fighters roam. Over 120,000 refugees who fled the invasion eke out a miserable life in five camps scattered in a forbidding corner of the Algerian desert. On the western side of the divide, Saharawis live in the underbelly of what the West likes to depict as a benevolent Moroccan regime. Freedoms of movement, expression, and assembly are denied; discrimination, arbitrary detentions, and beatings are routine occurrences. Amnesty International, Human Rights Watch, and the Robert F. Kennedy Center for Justice have repeatedly decried Moroccan human rights violations.

Ignoring international norms on resource exploitation in a territory under occupation, Morocco has also been selling the riches of Western Sahara. They range from valuable phosphate to desert sand, shipped in a steady flow to the shores of European beach resorts. In a highly profitable agreement, Morocco has also granted European Union fleets access to Western Sahara fishing grounds, among the richest in the world. And oil may soon be an additional perk for the occupier.