ICJ determines that the UK must end its administration of the Chagos Archipelago as rapidly as possible.


The International Court of Justice has today delivered its Advisory Opinion on the legal consequences of the separation of the Chagos Archipelago from Mauritius. The Court, by a majority of 13-1, found that the United Kingdom is under an obligation to bring an end to its administration of the Chagos Archipelago “as rapidly as possible”.

The Chagos Archipelago was detached from Mauritius by the British Government on 8 November 1965, when Mauritius was still a colony of the United Kingdom.  Mauritius attained it independent three years later on 12 March 1968. The UK administered the Chagos Archipelago as a new colony called the “British Indian Ocean Territory” and made the largest island, Diego Garcia, available to the United States for use as a military base.

The case was submitted to the Court by the United Nations General Assembly (UNGA) in June 2017. The UNGA, in a resolution endorsed by 94 States, formally requested that the Court answer two legal questions: (1) was the decolonisation of Mauritius lawfully completed? (2) If not, what are the legal consequences?

Speaking after the Court delivered its Opinion, Mauritius’ Prime Minister, H.E. Pravind Kumar Jugnauth said: “This is a historic moment for Mauritius and all its people, including the Chagossians who were unconscionably removed from their homeland and prevented from returning for the last half century. Our territorial integrity will now be made complete, and when that occurs, the Chagossians and their descendants will finally be able to return home.”

Professor Philippe Sands QC and Alison Macdonald QC represented Mauritius.