The fight to stop Keir Starmer’s controversial UK–Mauritius Chagos Islands agreement is intensifying, not only in the British courts and Parliament, but now also on Capitol Hill.
In a major development in Washington, the Republican-led U.S. House of Representatives Committee on Appropriations has formally raised concerns over the deal, highlighting its strategic implications for U.S. national security and the rising threat from Communist China.
Included in the recently released National Security, Department of State, and Related Programs Appropriations Bill for 2026, the Committee’s language makes clear that Diego Garcia remains a central pillar of Anglo-American power projection in the Indo-Pacific, and that the Chagos Islands deal now poses a serious risk to that posture.
NATIONAL SECURITY, DEPARTMENT OF STATE, AND RELATED PROGRAMS APPROPRIATIONS BILL, 2026:
“United Kingdom and Chagos Archipelago —The Committee notes that with the growing challenge from the PRC the military facilities on the island of Diego Garcia are central to Anglo-American power projection and relative control of the Indian Ocean. Recognizing the invaluable strategic importance and geographic relevance of Diego Garcia to the United States, the Committee encourages the Secretary of State to engage with His Majesty’s Government of the United Kingdom to ensure our long-term access to the facilities and that they remain integral to allied security.”
This explicit statement marks the first formal recognition in Congress of the threat posed by the Starmer Government’s agreement to hand over sovereignty of the Chagos Archipelago to Mauritius, a state bound by the Pelindaba Treaty, which prohibits nuclear weapons from being stationed or transiting its territory.
That treaty restriction includes Diego Garcia, once sovereignty formally transfers, meaning the UK and US could be legally blocked from deploying or supporting nuclear-capable assets from the base, even under a so-called “99-year lease.”
Claire Bullivant, CEO of the Great British PAC explains: “Don’t be fooled when Mauritius says, ‘You can still use the islands for nuclear weapons.’ Once they own the house, they can change the rules whenever they choose. Today it is ‘pay the rent and carry on.’ Tomorrow it is ‘no nukes, no exceptions.’ It is like renting from a landlord who suddenly bans pets. Their house, their rules.”
Strategic Fallout in Focus Ahead of Trump Visit
The update comes just weeks ahead of President Donald Trump’s expected State Visit to the United Kingdom in September, where Diego Garcia, China, and Indo-Pacific deterrence are likely to dominate behind-the-scenes discussions.
The Great British PAC, which has been campaigning against the agreement on both sides of the Atlantic, welcomed the move by the House Appropriations Committee. PAC officials confirmed that briefing documents have already been shared with President Trump’s team, as well as Vice President JD Vance and US national security advisor, Marco Rubio.
Bullivant continued:
“This is a glaring red alert for global security… but today brings a glimmer of hope. For the first time, we have clear, official confirmation from Capitol Hill that Washington is beginning to grasp the full scale of this unfolding disaster. This is no longer just a British concern, it’s a crisis for NATO, for the Five Eyes alliance, and for the entire Western deterrence posture. The threat to America’s forward presence in the Indo-Pacific is real and imminent. I’m enormously relieved that U.S. lawmakers are now engaged… because the window to act is closing fast.”
Nile Gardiner, who has been working closely with the Great British PAC on Capitol Hill outreach, commented:
“We can expect significantly increased scrutiny of the Starmer Government’s Chagos Islands deal on Capitol Hill, especially ahead of the upcoming State Visit to the UK in September by President Trump. The Chagos issue is not over in Washington, and major red flags are being raised in the United States.”
The Bigger Picture: Beijing Watching Closely
Critics warn that if the UK Government rushes to ratify the deal before the ongoing Judicial Review is heard, or before Parliament and Congress have been properly briefed, it will hand Beijing a global strategic victory. China, not Britain or America, will be the ultimate beneficiary of this reckless surrender.
Mauritius maintains a close economic relationship with Beijing, including a 2019 free trade agreement and significant Belt and Road-linked investments. Once sovereignty transfers, Port Louis will have the legal power to restrict or deny nuclear operations at Diego Garcia, potentially at China’s behest.
As previously reported, no national security impact assessment has been published by the UK Government, and Parliament was not given a meaningful opportunity to debate the full consequences of the treaty before it was pushed to second reading on July 15.
The UK High Court has yet to consider the Judicial Review submitted by Chagossian representatives — a legal challenge organised with the support of the Great British PAC. Despite an order from Mr Justice Johnson for the case to be expedited, the courts are now in summer recess until 1 October. As a result, the case may not be heard until November, by which point Parliament could have already ratified the deal.
The Fight Is Not Over
But today’s developments from Capitol Hill send a clear message: the Chagos issue is not going away, not in London and not in Washington. The Great British PAC and its allies on both sides of the Atlantic are calling for immediate action.
When Parliament returns, there must be:
- An immediate pause in legislative progress on the UK–Mauritius treaty,
- Full public disclosure of the legal and national security implications, and
- Urgent, coordinated US–UK engagement to ensure Diego Garcia remains an unimpeded base for allied operations, including nuclear deterrence.
This is not about tidying up a piece of colonial history. It is not about symbolism. As the U.S. House Appropriations Committee rightly warns, this is about preserving the cornerstone of allied power projection in the Indo-Pacific.
If the treaty is ratified before the courts have ruled and before Parliament or Congress have fully understood the implications, Britain and America will have surrendered one of the most strategically vital assets in the world, without a fight.
China is watching. Washington is waking up. And history is paying attention.
The question now is simple:
Will we act in time? Or look back, too late, at the moment we gave it all away?
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