UK and Mauritius Reach Historic Treaty on Chagos Islands Sovereignty

The United Kingdom and the Republic of Mauritius announced a historic bilateral agreement on Thursday, concluding decades of bitter diplomatic disputes by recognizing Mauritian sovereignty over the Chagos Archipelago. The landmark settlement resolves one of the last major decolonization disputes involving British imperial possessions in the Indian Ocean.

Under the terms of the treaty, announced jointly by British Prime Minister Keir Starmer and Mauritian Prime Minister Pravind Jugnauth, the UK will transfer legal title over the archipelago, previously designated as the British Indian Ocean Territory. In exchange, Mauritius will grant the UK an initial 99-year lease to maintain sovereignty and full operational control over the strategically vital atoll of Diego Garcia.

Decades of Colonial Sovereignty Disputes Concluded by Bilateral Accord

Diego Garcia hosts a joint UK-US defense facility that serves as a cornerstone of Western military power across the Indo-Pacific and Middle Eastern theaters. The agreement guarantees uninterrupted access for maritime reconnaissance, submarine servicing, and long-range bomber operations, relieving long-standing anxieties in London and Washington regarding judicial challenges at international tribunals.

The accord also addresses the humanitarian consequences of the forced displacement of the indigenous Chagossian population between 1968 and 1973. A new resettlement trust fund funded by the British government will provide financial compensation, infrastructure investment, and support for Chagossians seeking to visit or resettle on outer islands of the archipelago.

“This historic agreement secures the vital joint UK-US defense facility on Diego Garcia for future generations while rectifying a painful historical injustice and establishing a modern partnership with Mauritius.” — David Lammy, UK Secretary of State for Foreign, Commonwealth and Development Affairs

Strategic Security on Diego Garcia and Chagossian Resettlement Support

International bodies, including the International Court of Justice and the United Nations General Assembly, had repeatedly ruled that the UK's separation of the Chagos Islands from Mauritius prior to Mauritian independence in 1968 violated international law. The diplomatic compromise brings London into compliance with international legal consensus while insulating critical defense infrastructure.

Officials in Port Louis hailed the treaty as an enduring triumph of international diplomacy and national integrity. Both governments committed to finalizing the technical drafting of the treaty before year-end, opening a new chapter of environmental, economic, and security cooperation between the two Commonwealth nations.

Sources

• UK Foreign, Commonwealth & Development Office
• Prime Minister's Office of Mauritius