A private member’s bill intended to restrict the transfer of British sovereignty over the Chagos Islands has completed its second reading in the House of Lords, despite the Government rejecting its proposal for a referendum involving the Chagossian people.
The British Sovereignty Protection (Chagos Islands) Bill, introduced by Democratic Unionist Party peer Lord Weir of Ballyholme, was debated on Friday 23 October 2026. It was read a second time and committed to a Committee of the Whole House. The debate ended without a division, so the outcome was not a government defeat in a vote.
What the bill would do
The proposed legislation seeks to prevent the cession or transfer of sovereignty over the British Indian Ocean Territory without parliamentary approval and the consent of the Chagossian people. It would also provide for continued British sovereignty over the strategically important military base on Diego Garcia.
Lord Weir argued that decisions about the islands’ future should give greater weight to the wishes of Chagossians, many of whom were forcibly removed from their homeland during the 1960s and 1970s.
Government rejects referendum proposal
Responding for the Government, Foreign Office minister Baroness Winterton of Doncaster said ministers rejected the bill’s call for a referendum. She argued that entering into a treaty involved national security considerations and defended the Government’s approach to the Chagossian community and the strategic base.
The minister acknowledged the injustices experienced by Chagossians and said the Government continued to engage with different groups within the community. She also defended the arrangements negotiated with Mauritius, including provisions concerning the base and possible resettlement on islands other than Diego Garcia.
Background to the sovereignty dispute
The United Kingdom signed an agreement with Mauritius in 2025 under which Mauritius would be recognised as sovereign over the archipelago, while Britain would retain use of the Diego Garcia military base for an initial 99 years. The agreement became subject to renewed uncertainty in 2026, and the Government said in September that it would review the arrangement.
The dispute has a long international legal history. In 2019 the International Court of Justice issued an advisory opinion concerning the decolonisation of Mauritius, which the UK and Mauritius have interpreted differently in the wider sovereignty debate.
What happens next?
The bill now awaits detailed scrutiny at committee stage in the House of Lords. As a private member’s bill, it is not government legislation, and completing second reading does not mean its proposals will become law. It would still need to complete the remaining parliamentary stages and receive Royal Assent.
Sources: House of Lords Hansard, second reading debate (23 October 2026); UK Parliament, bill details; House of Lords Library research briefing (13 October 2026).