Key Takeaways:
- The UK has agreed to hand over the Chagos Islands to Mauritius, with the UK maintaining a 99-year lease of Diego Garcia.
- The deal has been met with criticism from some, including Donald Trump, who has described it as "an act of great stupidity".
- The UK government has argued that the agreement ensures the continued effective operation of the joint UK-US military base on Diego Garcia.
- The total projected cost of the finance package is estimated to be £3.4bn.
- Donald Trump’s criticism of the deal may be linked to his own territorial ambitions, including his claim on Greenland.
Introduction to the Chagos Islands
The Chagos Islands are an archipelago in the Indian Ocean, located about 5,800 miles south-east of the UK and 1,250 miles north-east of Mauritius. The islands have a complex history, having been part of British territory since 1814, when they were acquired by the UK as part of the Treaty of Paris after the defeat of Napoleon. In 1965, the islands were designated as British Indian Ocean Territory and detached from Mauritius, which became independent in 1968. The UK and Mauritius agreed that the islands would return to Mauritius once they were no longer needed for Britain’s defence. A joint UK-US military base was built on the largest of the islands, Diego Garcia, and displaced residents were resettled in Mauritius and Seychelles, while some were relocated to the UK in 2002.
The Return of the Chagos Islands to Mauritius
Since the 1980s, Mauritius has claimed sovereignty over the islands and pursued its case through international courts and tribunals. In 2019, the International Court of Justice (ICJ) ruled in a non-binding judgment that the process of decolonization of Mauritius was not lawfully completed when it was granted independence in 1968, and that the UK was "under an obligation to bring to an end its administration of the archipelago as rapidly as possible". Following this ruling, the UK and Mauritius began negotiations on the exercise of sovereignty over the Chagos archipelago. The UK government argued that having legal certainty over the Chagos Islands was essential for Britain’s defence, due to the risk of continued challenges in international courts. After 11 rounds of negotiations, a joint statement was published on October 3, 2024, announcing that a political agreement had been reached. The treaty was formally approved and signed by UK Prime Minister Keir Starmer and his Mauritian counterpart, Navin Ramgoolam, on May 22, 2025.
The Terms of the Deal
The deal between the UK and Mauritius allows Mauritius to take sovereignty of the islands, while the UK maintains an initial 99-year lease of Diego Garcia with an option of extension. The UK will pay for the lease, with an estimated average annual cost of £101m in 2025-26 prices. The total projected cost of the finance package is estimated to be £3.4bn. The UK government has argued that the agreement ensures the continued effective operation of the joint UK-US military base on Diego Garcia, which is essential for Britain’s defence. The deal has been met with criticism from some, including Donald Trump, who has described it as "an act of great stupidity".
Reaction to the Deal
The reaction to the deal has been mixed, with some criticizing the UK government for "handing over British territory" to Mauritius. The Conservatives, under the leadership of Kemi Badenoch, have described the deal as a "surrender" and argued that the UK is "paying upwards of £30bn to do so" to Mauritius, a country they claim "openly cuddles up to China and Russia". The US government, on the other hand, has issued a statement saying that the agreement "secures the long-term, stable, and effective operation of the joint US-UK military facility at Diego Garcia". Donald Trump’s criticism of the deal may be linked to his own territorial ambitions, including his claim on Greenland, which is part of the kingdom of Denmark.
Donald Trump’s Change of Heart
It is unclear why Donald Trump has changed his position on the deal, but it may be linked to his own territorial ambitions. Trump has been critical of the UK’s decision to hand over the Chagos Islands to Mauritius, describing it as "an act of great stupidity". He has also threatened to impose tariffs on European countries that oppose his claim on Greenland. The UK Prime Minister, Keir Starmer, has criticized Trump’s threats, saying that "threatening tariffs on allies is the wrong thing to do, completely wrong". The phone call between Starmer and Trump on Monday appears to have been tense, with Trump subsequently posting his criticism of the deal on Truth Social. It remains to be seen how the situation will develop, but it is clear that the deal has significant implications for the UK, Mauritius, and the US.