The UK and Mauritius are set to finalize a historic agreement that will transfer sovereignty of the Chagos Islands—also known as the British Indian Ocean Territory (BIOT)—to Mauritius, ending decades of legal and diplomatic disputes. The Chagos Islands UK Mauritius deal, scheduled for signing on Thursday, includes provisions for a long-term lease of the Diego Garcia military base to the UK and US.
Prime Minister Sir Keir Starmer will attend the virtual signing ceremony alongside Mauritian officials. In return for relinquishing the islands, Britain is expected to pay multi-billion-pound compensation, while retaining strategic control over the vital US-UK base on Diego Garcia for an initial period of 99 years.
Deal Overview
The Chagos Islands UK Mauritius deal grants Mauritius formal sovereignty over the archipelago while ensuring that Diego Garcia—used for joint UK-US military operations—remains operational. The agreement includes:
- A 99-year lease of Diego Garcia to the UK and US
- Billions in financial compensation to Mauritius
- Possible 40-year lease extension
- Provisions for Chagossian community engagement and resettlement discussions
The UK Foreign Office stated, “We are working to sign a deal which will safeguard the joint UK-US base on Diego Garcia, which is vital to our national security.”
Chagossian Community Involvement
In a significant gesture, the UK has invited six representatives from three Chagossian groups to meet with Europe Minister Stephen Doughty to discuss the implications of the deal and the future of Chagossian rights and resettlement.
An email sent to community representatives mentioned that the meeting would also focus on “FCDO’s Chagossian projects and the new Chagossian contact group”, although further details remain undisclosed.
Chagossians were forcibly removed from the islands between 1968 and 1973 to make way for the Diego Garcia military base, sparking a decades-long campaign for return and justice.
Political and Strategic Ramifications
While the agreement aligns with international legal opinions, including UN rulings backing Mauritius, it has drawn criticism from opposition parties like Reform UK and some Conservatives, who accuse the government of surrendering British territory.
However, Labour argues the deal protects UK interests: “The best way to guarantee the future of the military base was to do a deal with Mauritius,” officials stated.
US Secretary of State Marco Rubio and other Republicans initially opposed the plan, citing Mauritius’ growing ties with China. But with backing from President Trump last month, the deal gained crucial momentum.
Historical Context and International Pressure
The Chagos Archipelago was detached from Mauritius in 1965 while Mauritius was still a British colony. In exchange for independence in 1968, the islands were ceded to the UK for £3 million. Mauritius later declared this move illegal, claiming it was coerced as part of the decolonization process.
In 2019, the International Court of Justice (ICJ) ruled that the UK’s continued administration of the territory was unlawful. The UN General Assembly echoed this, urging the UK to end its colonial administration of the islands.
Despite these rulings, the UK retained control of the territory, citing security concerns over Diego Garcia—one of the most strategically important military bases in the world.
National Security and Strategic Importance
Diego Garcia serves as a critical node for US and UK operations in the Middle East, Africa, and South Asia, and houses naval and air force assets capable of rapid deployment.
Speaking in the House of Commons, Defence Secretary John Healey reiterated its importance: “The base on Diego Garcia is essential to our security and our security relationship with the United States.”
With the lease secured for at least 99 years, the UK believes it has struck a balance between international law and national security priorities.
What’s Next?
Following the signing, MPs will receive a full briefing on the deal’s specifics, including the scope of any lease extensions and financial commitments. The implementation phase is expected to involve:
- Continued diplomatic cooperation with Mauritius
- Legal finalization of sovereignty transfer
- Consultation with Chagossian diaspora regarding resettlement or compensation
- Final confirmation of the base lease terms with the US
The Chagos Islands UK Mauritius deal marks a turning point in Britain’s post-colonial foreign policy. While controversial, it aims to resolve a long-standing sovereignty dispute and ensure that the Diego Garcia base remains operational for the foreseeable future, maintaining the UK’s and the US’s strategic reach across the Indo-Pacific.
As global power dynamics evolve, this agreement could set a precedent for other post-colonial negotiations—balancing justice, geopolitics, and strategic defense.
