Advisory opinion on Western Sahara

The International Court of Justice Advisory Opinion on Western Sahara was a 1975 advisory, non-binding opinion by the International Court of Justice (ICJ) of two questions presented to it by the UN General Assembly under Resolution 3292 regarding the disputed territory of Western Sahara (then Spanish Sahara). Morocco had approached the UN to adjudicate its and Mauritania's claims over the territory.

Source: Wikipedia — Advisory opinion on Western Sahara (CC BY-SA 4.0)