An amendment to the EU (Withdrawal) Bill to prevent the Government from using sweeping powers to take Britain out of the EU agreements has been backed by the SNP, the Liberal Democrats, Plaid Cymru and the Green Party.
The move will be likely to expose deep divisions in Labour’s ranks over membership of the single market, days after Jeremy Corbyn came under fire from pro-EU MPs in his own party for taking the option off the table.
Labour MP Wes Streeting, who has been critical of Mr Corbyn’s leadership, used a speech on Saturday to warn that his party’s Brexit policy “stands as the single biggest barrier to the UK’s membership of the single market and customs union”.
It comes after Mr Corbyn was “empty chaired” at a cross-party summit on single-market membership which he refused to attend due to concerns it was “no more than a political gimmick”.
SNP Westminster leader, Ian Blackford, said: “Time is running out to prevent the economic catastrophe of an extreme Tory Brexit.
“We know UK government plans to drag Scotland and the UK out of the single market and customs union would destroy hundreds of thousands of jobs, and cause lasting damage to the incomes, livelihoods and living standards of millions of people across the country.
“With just 10 months to go before a deal is due between the UK and EU, sensible MPs of all parties must now unite to protect our vital place in the single market.”
The bill – which will move EU law onto the statute books after Brexit – returns to the Commons on Tuesday, after passing eight gruelling days of line-by-line scrutiny before Christmas.
It will have its report stage and third reading before moving onto the Lords, where pro-EU peers are expected to make trouble for the Government.
Liberal Democrat leader Sir Vince…