Ministers are to dramatically scale back the number of EU laws to be scrapped by the end of the year as part of Rishi Sunak’s bonfire of Brussels rules and regulations.

In a concession to opponents of the Retained EU Law Bill, Kemi Badenoch, the business secretary, is to publish a list of 800 laws which will be removed from the UK statute book in an attempt to get the legislation through the House of Lords.

The move has infuriated Brexiteer MPs, who warned that it would only amount to about 20 per cent of existing EU laws on the UK statute book. They accused Badenoch of being “unambitious” and giving in to peers who are threatening to neuter the legislation.

The compromise was revealed by Badenoch at a private briefing with members of the European Research Group (ERG) of Brexiteer MPs.

One of those present said she told the group that the concession was necessary to ensure that the bill became law before the next election amid fears that in its current form it will be effectively blocked by peers.

She is also said to have admitted that it was impossible to scrap more laws because civil servants had yet to analyse all the 4,000 pieces of legislation to determine whether they were still necessary.

Those laws which are not explicitly named on the list of 800 will remain on the statute book to be looked at again “in due course”. The government is also expected to commit to retaining the most high-profile EU-derived laws, including the working-time directive and environmental legislation.

One MP said Badenoch’s proposal had gone down like a “lead balloon” and would effectively end the government’s pledge of a post-Brexit bonfire of red tape that would see all 4,000 laws either scrapped, reformed or kept by the end of the year.

“She was basically saying that the civil service had not done the work and that we needed to be realistic about what we could achieve,” said one source who was briefed on the plans. “She admitted that it was a concession to the Lords to get the bill through. It went down like a lead balloon.”

Allies of Badenoch hit back, saying she had asked the ERG to come up with bad EU laws that they thought should be removed that were not included on the list of 800.

“The only thing they could come up with was product standards. She told them that as business secretary and as a mother that she thought that product standards were important.”

They added that Badenoch had acknowledged that the civil service could have done more to identify laws that could be scrapped but said each government department was responsible for assessing laws in their own individual areas.

They also insisted that the list of 800 included all the most important EU legislation which the government felt was in need of reform or scrapping altogether.

“She was only given this brief in February and is trying to achieve as much as she can. But these reviews were supposed to have been in train long before she took responsibility for this.”

Another source said Badenoch told MPs that Downing Street still wanted to press ahead with the bill without making concessions to the Lords but it was her view that concessions were necessary.

“To be fair she took responsibility for it,” said one of those present. “But seemed not to appreciate that her plan would turn the bill on its head. Rather than getting rid of all EU laws automatically, against a conscious decision to keep them was made by ministers this would get rid of a small number of EU laws with the presumption that you kept all the rest.

“That is not what the bill was intended to do.”

A government source said: “Kemi is a true Brexiteer . . . she’s a doer and not a talker. This government will pass the [Retained EU Law Bill] and end the supremacy of EU law in the UK, and if Brexiteers want delivery they should get behind what she’s doing.”