High Court Halts UK-Mauritius Deal Over Chagos Islands Amid Legal Challenge

Mace | 22nd May 2025 | Diplomacy, Embassy News, International
London,,Uk.,October,3,,2023.,British,Indian,Ocean,Territory,Flag

A High Court injunction has blocked the UK from finalising a sovereignty deal to transfer the Chagos Islands to Mauritius. The legal challenge, filed by a Chagossian-born British citizen, raises concerns over lack of consultation. The planned deal would retain the UK-US base on Diego Garcia for 99 years.

The United Kingdom's plan to transfer sovereignty of the Chagos Islands to Mauritius has been temporarily halted by a High Court injunction. The injunction was granted at 02:25 BST by Mr Justice Julian Goose, following an application from Bertrice Pompe, a British woman born on Diego Garcia, the largest island in the archipelago. The court order prevents the UK government from taking any legally binding steps to conclude negotiations concerning the possible transfer of the British Indian Ocean Territory until further notice. Prime Minister Sir Keir Starmer had been scheduled to participate in a virtual signing ceremony with Mauritian representatives on Thursday morning. The proposed agreement would see the UK hand over the Chagos Islands to Mauritius while allowing the UK and US to continue operating a military base on Diego Garcia for an initial period of 99 years. The financial terms of the deal have not been disclosed, but it is anticipated that the cost to British taxpayers will amount to billions of pounds. The legal action initiated by Pompe centres on concerns that the Chagossian community has not been adequately consulted regarding the sovereignty negotiations. Under both the current arrangement and the proposed deal, Chagossians are prohibited from returning to Diego Garcia, the largest island in the archipelago and the site of the UK-US military base. In response to the injunction, a government spokesperson stated that they do not comment on ongoing legal cases but emphasised that the deal is intended to protect British national security interests. Mauritius Attorney General Gavin Glover declined to comment, citing the ongoing legal proceedings. The Chagos Archipelago was separated from Mauritius in 1965, when Mauritius was still a British colony. Britain purchased the islands for £3 million, but Mauritius has argued that it was coerced into relinquishing the territory as a condition for gaining independence. In the late 1960s, the UK invited the US to establish a military base on Diego Garcia, leading to the removal of thousands of Chagossians from their homes. An immigration order issued in 1971 has since prevented the islanders from returning. The UK has faced increasing international pressure to return the islands to Mauritius, with both the United Nations' top court and General Assembly supporting Mauritius' sovereignty claims. Negotiations over the territory began under the previous Conservative government in late 2022 but were not concluded before the 2024 general election. The current Labour government has argued that unresolved questions about the UK's right to retain the islands pose a risk to the future of the US-UK military base. Opposition politicians have criticised the proposed deal, expressing concerns about Mauritius' close relationship with China and the financial implications for British taxpayers. Following the court's intervention, Conservative shadow foreign secretary Priti Patel described the situation as a "humiliation" for Prime Minister Starmer and Foreign Secretary David Lammy. Reform UK leader Nigel Farage questioned the necessity of the deal, suggesting it would cost approximately £52 billion and potentially benefit China.

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