Written question asked by Lord Callanan (Conservative) on Friday, 5 December 2025, in the House of Lords. It was due for an answer on Friday, 19 December 2025. It was answered by Baroness Chapman of Darlington (Labour) on Monday, 22 December 2025 on behalf of the Foreign, Commonwealth and Development Office.

Chagos Islands: Sovereignty

Question: To ask His Majesty's Government what assessment they have made of the impact of the Exchange of notes constituting an agreement between the Government of the United Kingdom of Great Britain and Northern Ireland and the Government of the United States of America concerning the availability for defence purposes of the British Indian Ocean Territory, London, 30 December 1966 on the legal status of the Chagos Archipelago, including the term that “The Territory shall remain under United Kingdom sovereignty”.

Answer: The Agreement between the UK and Mauritius secures the important UK-US military base on Diego Garcia. The Agreement was tested at the highest levels of the United States' security establishment, across multiple agencies, and it has been backed by our key allies and international partners, including the US and all our Five Eyes partners. Talks are ongoing to update the UK-US Exchange of Letters on the operation of the Diego Garcia Base. There are no agreements with the Maldives that would impact the operation of the base.

Secondary information

Type: Written question
Reference: HL12714
Session: 2024-26
Related items: Chagos Islands: USA
Tuesday, 10 February 2026
Written questions
House of Lords; British Indian Ocean Territory: Sovereignty
Wednesday, 11 February 2026
Written questions
House of Commons; British Indian Ocean Territory
Wednesday, 11 February 2026
Written questions
House of Commons
Grouped for answer: Yes
Subjects: Sovereignty USA Chagos Islands
Link: View this Written question on www.parliament.uk