Prime Minister Sir Keir Starmer's government has been dealt a significant blow, suffering four parliamentary defeats over its controversial plan to hand sovereignty of the Chagos Islands to Mauritius. The setbacks occurred in the House of Lords on Tuesday 6 January 2026, forcing the proposed legislation to return to the Commons for further scrutiny.
Four Key Defeats for the Government
The first defeat centred on the financial terms of the proposed 99-year lease for the strategic Diego Garcia military base. Peers backed an amendment, opposed by ministers, stating that the £101 million annual payments to Mauritius should cease if the UK and US could no longer use the base. The government lost the vote by eight.
A second blow came from the Liberal Democrats, who successfully amended the bill to require a referendum on the deal for Chagossians living in the UK. This was swiftly followed by a third defeat, as Tory peers forced through a measure demanding the government publish detailed costings of all payments to Mauritius.
The final defeat saw the Lib Dems secure another amendment, granting Parliament oversight of treaty-linked spending. This would allow MPs to halt payments to Mauritius if it breaches the deal's terms.
Security Concerns and Political Fallout
Shadow Foreign Secretary Dame Priti Patel condemned the legislation, stating Labour had faced a "humiliating defeat". She accused Sir Keir Starmer of being "weak and incapable of standing up for Britain" and warned that "Britain's defence and security are at risk because of this terrible legislation."
The government did narrowly avoid a fifth defeat, defeating a proposal that would have blocked the handover unless a majority of Chagossians supported it in a referendum.
Background of the Disputed Archipelago
The Chagos Islands, ceded to Britain in 1814, were formed into the British Indian Ocean Territory in 1965. The UK displaced the local population in the early 1970s to make way for the joint UK-US military base on Diego Garcia, which has since been a cornerstone of Western defence strategy.
Mauritius, which began negotiations with the UK in 2022 under the Conservative government, has long claimed sovereignty. The International Court of Justice has previously ruled that Britain is obliged to end its administration of the territory.
The bill will now return to the House of Commons, where the government will attempt to overturn the Lords' amendments and salvage its flagship foreign policy agreement.
