Diego Garcia Military Base and British Indian Ocean Territory Bill Committee: Clause 2 stand part

Parliament voted on 20 October 2025 to keep Clause 2 of the Diego Garcia Military Base and British Indian Ocean Territory Bill in the legislation, by 318 votes to 174. Clause 2 is the central provision dissolving the British Indian Ocean Territory as a British overseas territory in domestic law, and its removal would have gutted the Bill. The government won comfortably. The vote advances the UK-Mauritius Treaty signed on 22 May 2025, under which Mauritius becomes sovereign over the Chagos Archipelago, including Diego Garcia. Keeping Clause 2 in the Bill means the dissolution of BIOT proceeds once the Treaty enters into force, removing BIOT from the list of British overseas territories in the British Nationality Act 1981 and ending UK sovereignty over the islands. The Diego Garcia military base would continue to operate under rights granted by Mauritius rather than British sovereignty. The division broke sharply along party lines. All 272 voting Labour MPs and 33 Labour and Co-operative MPs backed the clause, along with Plaid Cymru, the Greens, and most other smaller parties. All 93 voting Conservatives, all 64 Liberal Democrats, and all 7 Reform UK MPs voted against, as did the Democratic Unionist Party. Opponents, led by the Conservatives, framed the Bill as a "surrender" of British territory for £35 billion, raising concerns about Chinese and Russian influence over Mauritius and the security of the Diego Garcia base. The Bill had already cleared related divisions on the same day, with amendments requiring publication of legal advice and risk assessments all defeated.