UK-Mauritius treaty on the Chagos Archipelago
The Chagos Archipelago has been the subject of a long-standing dispute over its sovereignty between the UK and Mauritius. Having been retained by the UK since 1965, the largest island, Diego Garcia, later became the site of a joint UK-US military base. In May 2025, the UK reached an agreement to transfer sovereignty of the islands back to Mauritius, while maintaining an initial 99-year lease of Diego Garcia. The agreement also includes security and financial provisions.
