The UK’s dependence on big American cloud providers poses “a strategic and economic vulnerability” to the country, politicians warned, as US authorities have the power to switch off Britain’s public services or demand personal information under federal law.

Some of the UK’s most critical public services such as health, defense and tax administration are migrating to US clouds, raising concern among Members of Parliament. The unpredictable Trump administration makes the issue particularly urgent, they said.

Chi Onwurah, chair of the UK parliament’s science, innovation and technology committee, told Bloomberg that Washington effectively holds a legal “kill switch” in the form of the US CLOUD Act, which overrides UK privacy and data protection laws.

Under the legislation, US-headquartered providers can be made todisclose personal data on their servers if the government declares someone a threat, the committee was told by experts. The US can also order providers to withhold or withdraw services.

Earlier this year the committee warned that as a result British public services could be “derailed at any time by a decision taken outside our shores.”Onwurah said recent White House decisions to block Anthropic and OpenAI from sharing tools with the UK revealed the potential threat. “The president could kill parts of critical national infrastructure by turning it off,” she said.

However, it’s “unlikely the UK could build a national competitor” to the services provided by US tech giants on its own, Onwurah added. “We should be working with France and Germany.”Sovereignty is becoming an increasingly urgent issue as the UK tries to take advantage of AI, which requires access to the cloud for the computing power needed to process data. Kanishka Narayan, the AI minister, said last week that Britain needs around six times its current level of power just to cover basic requirements.

Only a massive data center roll-out could deliver that, but AI hyperscalers already face a backlash. Last month, the Scottish government voted to pause all new hyperscale data center developments, putting 24 projects on hold. Residents in other parts of the UK have also protested against data centers, mirroring the political fallout in the US.

Cloud security could be one way of changing the public mood. “The thing the British public really doesn’t like is their private sensitive data, particularly their healthcare data, going to foreign billionaires,” Narayan said.

The UK government spends about £1 billion ($1.3 billion) a year on cloud services, according to estimates from the committee, and is particularly dependent on AWS and Microsoft. Onwurah said those two providers alone account for as much as 80% of cloud services bought by the UK government but officials “don’t know the exact level of dependence.”In the past year, HM Revenue & Customs awarded AWS a £473 million 10-year contract to manage UK tax data and the defense ministry struck a £400 million deal with Google Cloud to “strengthen secure communication links between the UK and US.”

National Health Service trusts are migrating patient records from servers to US clouds.

The dominance of the large US cloud providers is raising competition concerns, with some experts warning that sector poses a far greater monopoly risk in the UK than AI itself, where there is more plurality. “On this question of monopoly, the place where you can see more concentration is the cloud providers themselves,” James Benford, director general of economic statistics at the Office for National Statistics, told a recent conference in London.

Onwurah believes the government is “not getting value for money.”A government spokesperson said officials were working “to strengthen resilience and improve the way the public sector procures and manages cloud services” and that departments must consider “risks associated with over-reliance on any individual supplier.”All three departments said their data was safeguarded in UK domiciled data centers, in response to queries from Bloomberg, but did not address the US CLOUD Act concerns directly.

Other European countries are taking a more forceful approach than the UK, prompted in part by testimony from Microsoft France’s legal director in 2025 in which he accepted the company would not be able to oppose a US injunction demanding access to French citizens’ personal information.

The European Commission is developing its own framework under the Cloud and AI Development Act to “strengthen Europe’s sovereignty and competitiveness in the cloud and AI ecosystem” by encouraging greater use of the continent’s infrastructure.

In April, France replaced Microsoft Azure with domestic cloud provider Scaleway for its national health data hub and has developed OVHcloud, a sovereign cloud service. The German state of Schleswig-Holstein has moved from Microsoft to open-source alternatives. However, even European alternatives are tiny compared with their US rivals. OVHcloud had just about €1 billion in revenue last year. AWS had $128 billion.

HMRC said its cloud contracts have to meet “strict government security, data protection and procurement requirements.”The MOD said contracts were subject to “strict data sovereignty and security controls.”DHSC said protecting patient data was “an absolute priority” and all NHS organizations “must comply with UK data protection law.”