UK cedes Chagos Islands’ sovereignty to Mauritius, keeps base; India hails deal

India “welcomed” the agreement, saying it “completes the decolonisation of Mauritius”.

Sources in New Delhi said India “played a quiet but important role in the background”. “It firmly backed the principled Mauritian position, supporting its stance on the need to do away with the last vestiges of colonisation. At the same time, it consistently encouraged both sides to negotiate with an open mind and with a view to achieving mutually beneficial outcomes. It is believed that the final outcome is a win for all sides involved and will reinforce long term security in the Indian Ocean region,” sources said.

The joint statement issued by Mauritius and the UK acknowledged India’s role: “In reaching today’s political agreement, we have enjoyed the full support and assistance of our close partners, the United States of America and the Republic of India.”

This week’s political agreement is subject to a treaty and supporting legal instruments being finalised. Both sides have committed to complete this as quickly as possible, it said.

“Under the terms of this treaty, the UK will agree that Mauritius is sovereign over the Chagos Archipelago, including Diego Garcia. At the same time, both our countries are committed to the need, and will agree in the treaty, to ensure the long-term, secure and effective operation of the existing base on Diego Garcia which plays a vital role in regional and global security. For an initial period of 99 years, the UK will be authorised to exercise with respect to Diego Garcia the sovereign rights and authorities of Mauritius required to ensure the continued operation of the base well into the next century,” it said.

“The treaty will address wrongs of the past and demonstrate the commitment of both parties to support the welfare of Chagossians. Mauritius will now be free to implement a programme of resettlement on the islands of the Chagos Archipelago, other than Diego Garcia, and the UK will capitalise a new trust fund, as well as separately provide other support, for the benefit of Chagossians,” it said.

This is a “seminal moment in our relationship and a demonstration of our enduring commitment to the peaceful resolution of disputes and the rule of law. Negotiations have been conducted in a constructive and respectful manner, as equal sovereign States, on the basis of international law, and with the intention of resolving all outstanding issues between the UK and Mauritius concerning the Chagos Archipelago, including those relating to its former inhabitants,” the joint statement said.

Britain, which has controlled the region since 1814, detached the Chagos Islands in 1965 from Mauritius — a former colony that became independent three years later — to create the British Indian Ocean Territory.

In the early 1970s, Britain evicted almost 2,000 residents to Mauritius and the Seychelles to make way for an airbase on Diego Garcia, which it had leased to the US in 1966. In 2016, Britain’s Foreign Ministry extended Diego Garcia’s lease until 2036, and declared the expelled islanders would not be allowed to go back.

Thursday’s agreement said Mauritius would be free to implement a programme of resettlement on the islands other than Diego Garcia, with the terms left for Port Louis to decide.

“We were guided by our conviction to complete the decolonisation of our republic,” Mauritian Prime Minister Pravind Jugnauth said in a televised speech.

According to the British statement, the agreement underpins the UK’s commitment to safeguarding global security, with the operation of the military base unchanged, “in an increasingly volatile world”. This is seen to be a reference to China’s foray in the Indian Ocean.

It said the agreement is supported by international partners including the US, which has joint operation of the strategic military base.

“Without today’s agreement, the long-term, secure operation of the military base would be under threat, with contested sovereignty and legal challenges — including through various international courts and tribunals. The agreement demonstrates the UK Government’s commitment to safeguarding global security and averting threats to peace and prosperity in the Indian Ocean and wider Indo-Pacific. It sees Mauritius assume sovereignty over the islands, with the UK authorised to exercise the sovereign rights of Mauritius on Diego Garcia,” it said.

“This government inherited a situation where the long-term, secure operation of the Diego Garcia military base was under threat, with contested sovereignty and ongoing legal challenges. Today’s agreement secures this vital military base for the future. It will strengthen our role in safeguarding global security, shut down any possibility of the Indian Ocean being used as a dangerous illegal migration route to the UK, as well as guaranteeing our long-term relationship with Mauritius, a close Commonwealth partner,” UK Foreign Secretary David Lammy said.

“Welcome deal today between the UK and Mauritius. This agreement enables deeper cooperation with India in the Indian Ocean, strengthening global security and averting threats to peace and prosperity in the wider Indo-Pacific,” Lindy Cameron, British High Commissioner to India, said in a post on X.

“We welcome the agreement between the UK and Mauritius on the return of Mauritian sovereignty over the Chagos archipelago, including Diego Garcia. This significant understanding completes the decolonisation of Mauritius. The resolution of the longstanding Chagos dispute after two years of negotiations, in compliance with international law, is a welcome development,” the Ministry of External Affairs (MEA) said in a statement.

“India has consistently supported Mauritius’s claim for sovereignty over Chagos, in line with its principled stand on decolonisation and support for the sovereignty and territorial integrity of nations, as well as its longstanding and close partnership with Mauritius. India remains committed to working with Mauritius and other like-minded partners in strengthening maritime safety and security and contributing to enhanced peace and prosperity in the Indian Ocean region,” it said.

US President Joe Biden welcomed the deal, saying it would secure the effective operation of the Diego Garcia airbase.

The UK-Mauritius joint statement said the agreement would herald a new era of economic, security and environmental partnership between the two countries. To enable this partnership, the UK will provide a package of “financial support to Mauritius”.

The UK and Mauritius will cooperate on environmental protection, maritime security, combating illegal fishing, irregular migration and drug and people trafficking within the Chagos Archipelago, with the shared objective of securing and protecting one of the world’s most important marine environments. This will include the establishment of a Mauritian Marine Protected Area.

“In resolving all outstanding issues between the UK and Mauritius, the treaty will open a new chapter in our shared history, one which will continue to be based on mutual respect and trust as close Commonwealth partners committed to the security and prosperity of the Indian Ocean Region,” it said.