Ministers have scrapped their promise to replace all EU-era laws by the end of this year.
The Retained EU Law (REUL) Bill was introduced under Liz Truss and Jacob Rees-Mogg with the intention of removing all EU legislation from the UK by the end of 2023 after the UK left the bloc in 2020.
Kemi Badenoch, the business and trade secretary, has now revealed fewer than 600 laws will be revoked under the bill by the end of the year instead of the 4,000 or so pledged.
She acknowledged there are “risks of legal uncertainty” by automatically scrapping the laws by the end of 2023.
Ms Badenoch said it is “about more than a race to a deadline” and instead of looking for laws that need to be saved, the government will keep existing laws and look for those it can remove without causing problems.
She told parliament in a written statement: “Over the past year, Whitehall departments have been working hard to identify retained EU law to preserve, reform or revoke.
“However, with the growing volume of REUL being identified, and the risks of legal uncertainty posed by sunsetting instruments made under EU law, it has become clear that the programme was becoming more about reducing legal risk by preserving EU laws than prioritising meaningful reform.
“That is why today I am proposing a new approach: one that will ensure ministers and officials can focus more on reforming REUL, and doing that faster.”
The move will likely infuriate Tory Brexiteers who wanted to withdraw the UK from the EU’s influence, but will be welcomed by critics who warned the project was unfeasible and important regulations would be scrapped without proper scrutiny.
Animal charity the RSPCA said it was a “great win” for animals as the plan could have wiped out 44 animal welfare laws brought in while the UK was in the EU, including bans on battery hens and the importation of meat produced with growth promoters.
Labour’s shadow Cabinet Office minister Jenny Chapman, said it was a “humiliating U-turn from a weak and divided government with no clue how to grow our economy, protect workers, support business or build a better Britain outside the EU”.
Mr Rees-Mogg, who introduced the bill to remove EU laws, accused Rishi Sunak of breaking his promise.
The former business secretary said: “Regrettably the prime minister has shredded his own promise rather than EU laws.”
He added that instead of reviewing or appealing all EU laws “in his first hundred days”, Mr Sunak “has decided to keep nearly 90% of retained EU law”.
“This is an admission of administrative failure, an inability of Whitehall to do the necessary work and an incapability of ministers to push this through their own departments.
“Regrettably, ‘the blob’ has triumphed and the prime minister has abandoned his promise.”
During Mr Sunak’s leadership campaign last summer, he released a video showing piles of papers marked “EU legislation” being put through a shredder.
The video said: “In his first 100 days as prime minister, Rishi Sunak will review or repeal post-Brexit EU laws.
“All 2,400 of them.
“Keep Brexit safe. Vote Rishi Sunak today.”
Eurosceptic MPs were told last month the plan to scrap swathes of laws had been changed.
The Lib Dems said the government has dug itself into a hole by U-turning on their plans.
Lord Fox, the party’s lead on the bill in the House of Lords, said: “The Conservative government have dug themselves into a hole with this Retained EU Law Bill. While they may have stopped digging, they’re still in the hole.
“In their desperate attempts to avoid this legislation turning into chaos, they’re still leaving a lot of uncertainty. Both the public and businesses should be able to go on without being constantly concerned by the precariousness of so many of our laws.”
He said the Lib Dems will continue to fight to remove “as much of this uncertainty as possible” and will push “to retain our environmental safeguards, food standards and employment protections”.