Boris Johnson's plan to allow British judges to overturn European Court of Justice (ECJ) rulings after Brexit is inappropriate and it should be stripped from the legislation, a senior group of peers has warned.

Members of the Lords Constitution Committee sounded the alarm over the prime minister's plan to rip up Theresa May’s commitment to transfer all EU law onto the domestic statute books, which meant it could only be overturned by the Supreme Court or the High Court of Justiciary in Scotland.

Instead, Mr Johnson added a clause into the Withdrawal Agreement Bill (WAB) - which is undergoing Lords scrutiny ahead of the 31 January Brexit deadline - to allow ministers the power to direct the courts on interpretation of EU law and to allow lower courts the power to overturn ECJ rulings.

The committee, which includes several Conservative peers, said the move raised "substantial constitutional concerns" and urged the government to scrap it from the legislation, setting up for a showdown over the bill in the upper chamber.

Mr Johnson's Brexit deal sailed through its Commons stages with an overwhelming majority last week but it must undergo line-by-line scrutiny in the Lords before it can become law.

Guiding the bill through the Lords unscathed will be a tougher challenge for the prime minister, where the Tories have no majority to force through their legislative agenda.

In a critical new report, the Lords committee said: "We do not believe it is appropriate for courts other than the Supreme Court and the Scottish High Court of Justiciary to have power to depart from the interpretations of EU case law.

"Allowing lower courts to reinterpret EU case law risks causing significant legal uncertainty that would be damaging to individuals and companies."

It adds: "We cannot see the case for such broad and constitutionally significant regulation-making powers, and are not convinced by the rationale offered by the government."

Trade unions previously warned that allowing British courts to overturn ECJ rulings could allow exploitative bosses to try to challenge protections for low paid workers, which are enshrined in EU law.

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Labour peer Baroness Taylor, who chairs the committee, said: “The government should reconsider the implications of clause 26 and the potential for significant legal uncertainty if lower courts are to be given the power to depart from previous CJEU case law and previous domestic interpretations of retained EU law.

"The government should also provide for a sifting process for the scrutiny of instruments made under the bill, as recommended by the Delegated Powers and Regulatory Reform Committee.”

Liberal Democrat MP Alistair Carmichael said the report was "damning in its indictment of Boris Johnson's recklessness" towards Brexit.

He told The Independent: “Handing ministers unchecked power and removing parliamentary scrutiny is a dangerous move that risks undermining our democracy. It shows that this Conservative government are determined to continue to try and ride roughshod over our institutions to their own end.

"We have checks and balances in place for a reason. If Boris Johnson's deal is as good as he says, there is no reason to give lower courts these powers creating grey areas, if not complete legal limbo."

Attempts to amend the Brexit legislation are likely to come next week, when peers move onto the report stage of the bill.

Meanwhile, Mr Johnson insisted it was "epically likely" that the UK would be able strike a comprehensive EU trade deal by the end of the transition period in December 2020.

He told BBC Breakfast: "Obviously you always have to budget for a complete failure of common sense, that goes without saying, but I'm very, very, very confident that we'll get a (deal).

"This is not about a deal, this is about building a great new partnership. And from January 31, what we're going to do is start working with our friends and partners around the world - not just with the EU.