On 3 November 2022 the UK Secretary of State for Foreign, Commonwealth and Development Affairs made a written ministerial statement in the House of Commons (HCWS354), repeated in the House of Lords (HLWS347), whereby the minister confirmed:
“[T]he UK and Mauritius have decided to begin negotiations on the exercise of sovereignty over the British Indian Ocean Territory (BIOT)/Chagos Archipelago.
Through negotiations, taking into account relevant legal proceedings, it is our intention to secure an agreement on the basis of international law to resolve all outstanding issues, including those relating to the former inhabitants of the Chagos Archipelago.
[…]
The UK and Mauritius have agreed to engage in constructive negotiations, with a view to arriving at an agreement by early next year.”
HCWS354
Relevant legal proceedings would include domestic proceedings, and at the international level: Chagos Marine Protected Area Arbitration; Delimitation of the maritime boundary in the Indian Ocean (and related Preliminary Objections proceedings) and the Legal Consequences of the Separation of the Chagos Archipelago from Mauritius in 1965 (Advisory Opinion).
Of further note, the negotiations are framed around statements that the UK will seek to “strengthen significantly” its cooperation in the Indian Ocean on a range of issues, and “The UK and Mauritius have reiterated that any agreement between our two countries will ensure the continued effective operation of the joint UK/US military base on Diego Garcia”. The USA and India will be kept informed of progress in negotiations and the operation of the military base on Diego Garcia.
De Maribus 