David Davis has been warned by senior Tories that they are “deadly serious” about pushing the Government into enshrining Britain’s Brexit deal in law.

Ex-cabinet minister Nicky Morgan told Brexit Secretary Mr Davis that Conservative rebels would not ease pressure on the Government to make the concession.

The plan to force the Government to pass a further major piece of Brexit legislation was proposed by senior Tory Dominic Grieve, but was also supported on Thursday by Labour’s Sir Keir Starmer.

It comes as the Government confirmed its current piece of Brexit legislation, the EU (withdrawal) Bill will finally come before the House of Commons again in three weeks after MPs from all parties made 400 attempts to change it.

Meanwhile, ministers also signalled they would bring forward further legislation setting out how the UK’s transition out of the EU would work – in a move that gives Parliament greater sway over that process.

Mr Davis was appearing in the Commons after sparking anger on Wednesday by saying MPs may not vote on any Brexit deal until after the UK has left the EU, but was later forced into a retraction when Downing Street intervened to prevent a bigger row.

The fracas saw support for Mr Grieve’s plan consolidate, as MPs feared ministers could try and sideline Parliament as the Brexit process goes on.

Brexit: the deciders Show all 8 1 /8 Brexit: the deciders Brexit: the deciders European Union's chief Brexit negotiator, Michel Barnier Getty Brexit: the deciders French President Emmanuel Macron Getty Brexit: the deciders German Chancellor Angela Merkel Reuters Brexit: the deciders Commission President Jean-Claude Juncker EPA Brexit: the deciders The European Parliament's chief Brexit negotiator Guy Verhofstadt Getty Brexit: the deciders Britain's Prime Minister Theresa May Getty Images Brexit: the deciders Britain's Chancellor of the Exchequer, Philip Hammond PA Brexit: the deciders After the first and second appointed Brexit secretaries resigned (David Davis and Dominic Raab respectively), Stephen Barclay is currently heading up the position PA

Ms Morgan told Mr Davis he should allay MPs’ concerns by accepting the plan to enshrine the final Brexit deal in law – with ministers currently only promising to give the Commons a vote to accept Theresa May’s deal, or drop out of the EU with no deal.

She went on: “Reports have reached members on this side that the Secretary of State does not think that those Conservative members who have signed that amendment are serious about supporting it if we need to.

“Can I tell him – we are deadly serious.”

The MP, who also chairs the influential Treasury Committee, added: “It would be better for the Government to adopt a concession strategy on having a withdrawal agreement secured by statute, sooner rather than later, for all concerned.”

Mr Davis said the reports Ms Morgan referred to were not true, but he also came under pressure from Mr Grieve himself.

The ex-attorney general said: “Is it not the reality that if this negotiation leads to an agreement then it is necessary for both the European Parliament, but also ourselves, to act in accordance with our constitutional principles in deciding to approve it.

“The only way we can do that properly is by statute in this House.”

David Davis: Parliament may not get vote on final Brexit deal until after Brexit happens

The Independent first reported earlier this month that the Government is actively considering further legislation as a concession to Tory rebels, with Ms May’s Commons majority wafer thin.

If they do not give some ground they will face an alliance of Tory backbenchers and Labour, with Shadow Brexit Secretary Sir Keir confirming on Thursday that his party would back Mr Grieve’s proposals for a final piece of legislation on Brexit.

Sir Keir mocked Mr Davis over his embarrassing climbdown on Wednesday, in which he was forced to eventually say it is the Government’s intention to let Parliament vote on Ms May’s Brexit deal before it leaves the EU.

“What a mess. One thing one day, another thing the next,” said Sir Keir.

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He went on: “The Secretary of State has repeatedly asked us to accept his word at the dispatch box.

“Given the events of the last 24 hours, will he now accept the amendments that are done to the withdrawal bill, that the Article 50 meaningful vote should be put into law, so that we all know where we stand and we don’t have to repeat this exercise?”

Mr Davis responded: “We’ve said it is our intent and our expectation, those are the words used, I crafted them, our intent and expectation that we will vote on this in this House, before the European Parliament – that stands.”