UK businesses face a “storm” of flawed and poorly scrutinised laws, rushed through by government ministers with minimal parliamentary oversight after Brexit, top lawyers have warned.

Thousands of pieces of legislation must be amended or else they simply will not apply after 29 March 2019 when the UK leaves the EU. With Brexit taking up much of the government and parliament’s time, the task of trawling through laws to make these changes will be rushed and mistakes “undoubtedly” made, many of which won’t be noticed until they are in force, Hogan Lovells said.

It warned that it was looking increasingly likely that the process of redrafting legislation would take place within government departments and without appropriate consultation.

Analysis by the law firm outlines the sheer scale of the task facing the government. Some 19,000 pieces of EU legislation must be replicated, touching all aspects of life from health and safety to harbours and highways; from employment rights to exotic diseases.

A further 7,900 statutory instruments that implement EU laws in the UK are also affected, along with 759 bilateral treaties and 41 European agencies that must be replicated.

Charles Brasted, a partner at Hogan Lovells said businesses need to be more vigilant than ever before about mistakes that could affect them.

He warned that even minor changes to the wording of a provision could dramatically alter the application of rules.

The broad application of so-called Henry VIII powers which allow the government to enact legislation is controversial.

The Brexit department estimates that between 800 and 1,000 “corrections” will need to be passed by statutory instrument, which allows for laws to be made without a parliamentary vote.

Ministers have claimed that the power to “correct deficiencies” in retained EU law is justified because the process is purely a mechanical exercise of making sure the statute works when the UK is outside the trading bloc. But Mr Brasted said these decisions inevitably involve policy choices.

“The Government truly has a mammoth task ahead of it and will need to work quickly to complete the largest legislative overhaul ever undertaken in the UK which will fundamentally change the legal and regulatory environment of businesses across the country,” he said.