evidence: Chagos Islands dispute: Mauritius calls US and UK 'hypocrites' [...] In an advisory opinion in February 2019 the ICJ said that the archipelago should be handed over to Mauritius in order to complete its "decolonisation". [...] The Chagos Archipelago was separated from Mauritius in 1965, when Mauritius was still a British colony. Britain purchased it for £3m - creating the BIOT.