May 22, 2025: The UK has agreed to transfer sovereignty of the Chagos Islands to Mauritius after more than five decades of contested ownership and international pressure. Prime Minister Keir Starmer signed the agreement, which marks a major geopolitical shift in the Indian Ocean and formally ends one of the UK’s most protracted post-colonial disputes.

Structure of the Agreement
Under the terms of the deal, Britain will cede formal control of the Chagos Archipelago but retain a 99-year lease on Diego Garcia, the largest island in the chain, which hosts a significant U.S.–UK military base. The lease arrangement ensures the continuity of Western defense operations while acknowledging Mauritian sovereignty.

The UK has agreed to compensation and logistical support for Mauritians displaced during the 1960s and 1970s. Many of them were forcibly removed to allow the construction of the Diego Garcia base. The deal includes phased resettlement rights and provisions for Chagossian descendants to return under Mauritian governance.

Judicial and Political Hurdles
A British High Court injunction sought by a group of claimants opposing the handover temporarily delayed the agreement. Days later, the injunction was lifted, allowing the UK to proceed. Legal observers note that the case revealed ongoing tensions between executive foreign policy decisions and domestic judicial review.

Domestically, the move has received mixed political reactions. Labor leadership framed the handover as a restorative act of international justice, while critics in the Conservative bloc warned of security risks and strategic concessions.

Regional and International Reactions
Mauritius has welcomed the agreement as a long-awaited validation of sovereignty claims repeatedly upheld by the International Court of Justice and United Nations General Assembly. India, France, and several African Union members issued statements of support, seeing the transfer as a precedent for resolving other colonial-era territorial disputes.

The U.S. has not objected to the sovereignty shift, given the secured lease on Diego Garcia. However, analysts warn that future instability in Mauritius or policy shifts affecting the base could lead to broader strategic implications across the Indo-Pacific.