A Labour spokesman said this afternoon that while the party "fully respects" the referendum result its MPs would be asked to oppose the legislation which unamended would "let government ministers grab powers from parliament to slash people's rights".
Shadow Brexit secretary Sir Keir Starmer said the current state of affairs and the slow progress so far were a "real cause for concern" because withdrawal from the European Union without a deal could be a possibility by the last stage of the talks next month.
Others suggested Mr Corbyn has only ordered his Labour MPs to vote against the EU (Withdrawal) Bill because he knows he does not have the numbers to defeat the Government at the second reading vote next Monday evening.
Chris Grayling, the transport secretary, this morning said the legislation was needed to prevent "complete legal vacuum" and a "legal cliff edge" when the United Kingdom leaves the EU.
Opening the Commons debate, which concludes with a vote next Monday, the Brexit Secretary will promise to work with MPs as well as welcoming scrutiny and debate on the Bill at its second reading and then in its committee stage.
Team Sky's Chris Froome closes on Vuelta a Espana victory
Four bonus seconds to Nibali that's alright - I'll take that for today and safe my legs for tomorrow. Trentin also won the fourth and 10th stages.
The Observer newspaper cited unnamed parliamentarians, including former ministers, as saying there was growing anger among pro-European Conservatives as they are told that softening the repeal bill with be seen as backing Labour, making a leadership challenge against May more likely this autumn. On Feb. 2, May's deputy advised Conservative lawmakers against doing anything that would increase Labour's chances of returning to power, while May said the bill was the best way to ensure a successful Brexit.
A Conservative backbench rebellion is growing over "Henry VII powers" granted to ministers in it that allow them to modify huge chunks of European Union law without MPs' scrutiny.
A Labour spokesman said: "Nobody voted in last year's referendum to give this Conservative government sweeping powers to change laws by the back door".
Remainers including Dominic Grieve QC, Anna Soubry and Nicky Morgan have warned that they will not support the legislation being used as a "power grab", with ministers permitted to amend laws "by decree". The slogan of the Leave campaign was about people taking back control and restoring powers to parliament. "It would allow the government to seize control from the parliament that the British people have just elected".
In an August 31 debate, the main opposition Labour Party is planning to propose several changes to the repeal bill with a view to keeping Britain in the single market and customs union during a Brexit transition period after 2019, according to The Times.