Sir Keir Starmer has cancelled more than £1bn in funding for supercomputer projects announced under the previous Conservative government.
The Department for Science, Innovation and Technology (DSIT) said it would not take forward £800m earmarked to build Britain’s most powerful supercomputer in Edinburgh.
It has also dropped a plan to spend £500m on artificial intelligence computing announced earlier this year.
The Government said it was making “difficult and necessary spending decisions” and that commitments by the previous government had been unfunded.
However, the decision was criticised by the Conservatives as “extremely short sighted”.
Britain’s biggest supercomputer, the Archer 2 facility in Edinburgh, ranks 49th in the global rankings but the most powerful US computer, Frontier, is more than 60 times as powerful.
The £800m had been promised for a successor that would be 50 times more powerful and work had already begun on building it, but the project is now believed to be on hold.
It is understood that funding is likely to be reassessed in the future.
‘Extremely short sighted’
“The decision to scrap the UK exascale computer is extremely short sighted,” said Alex Burghart, the shadow Northern Ireland secretary.
“Exascale would have put top-tier technology at the disposal of UK researchers & businesses – and was key to having next gen AI research in Britain.”
Andrew Griffith, the shadow science and technology secretary, suggested that Labour has “lower ambitions for the UK tech sector”. He said the science and technology department was likely to underspend its budget at the point the election had been called.
The last government committed £300m to AI computing resources at Bristol and Cambridge universities, and said earlier this year it planned to spend an extra £500m. The second part of this has also been dropped.
An industry source said: “At a time when funding for AI and compute resources is increasing across the world, this is an alarming backward step for the country.”
It is understood that funding for both projects is likely to be reassessed as part of a review of the Government’s AI plans.
A DSIT spokesman said: “We are absolutely committed to building technology infrastructure that delivers growth and opportunity for people across the UK.
“The Government is taking difficult and necessary spending decisions across all departments in the face of billions of pounds of unfunded commitments. This is essential to restore economic stability and deliver our national mission for growth.
“We have launched the AI Opportunities Action Plan which will identify how we can bolster our compute infrastructure to better suit our needs and consider how AI and other emerging technologies can best support our new Industrial Strategy.”