Conservative MPs are to be given a free vote as the House of Commons seeks an alternative to Theresa May’s EU withdrawal deal, but Cabinet ministers will be told to abstain.

MPs are set to take back control of the Brexit agenda on Monday in a second round of “indicative” votes on a series of rival proposals tabled by backbenchers, to see if any can command a majority.

Alternatives on offer include a customs agreement with the EU, a second referendum on any deal and a power for MPs to vote to block a no-deal Brexit.

If a majority coalesces behind any plan, MPs are expected to seek to pass legislation on Wednesday to try to force the Government to act on it.

The move comes as Mrs May struggles to contain the rising tensions with her Cabinet as the clock counts down to the latest EU deadline on April 12.

Despite seeing her deal again defeated on Friday, the Prime Minister is determined to bring it back to the Commons for a fourth time in a final roll of the dice to get it over the line.

Downing Street sources confirmed that the Government will whip against the business motion enabling Monday’s indicative votes to go ahead.

She has previously warned that the unusual procedure – first used on Brexit last Wednesday without producing a majority for any option – risks creating a harmful constitutional precedent.

Mrs May spent the weekend trying to build support among MPs who could be won over, with aides saying she was “100% focused” on getting the result she needed.

‘Indicative votes’ what could happen
(PA Graphics)

Some in Parliament believe that if MPs begin to gather around a “softer” Brexit, it may finally convince Brexiteer hold-outs that the PM’s deal now represents the “hardest” break with the EU available.

But Democratic Unionist Party Brexit spokesman Sammy Wilson insisted the party would continue to vote against Mrs May’s EU withdrawal deal, which he said would “would take us away from the country that we fought to stay part of”.

The pro-EU Justice Secretary David Gauke warned Mrs May not to ignore the will of Parliament if it does swing behind a “softer” deal such as the customs union plan proposed by Tory veteran Ken Clarke, which came closest to gaining a majority in the first round of indicative votes.

In an open letter to MPs, the chief executive of Siemens UK urged them to unite around a “customs union compromise” which he said was “essential” to frictionless trade and would save companies billions each year.

Juergen Maier warned that the UK used to be a “beacon for stability”, but is now becoming a “laughing stock”.

His comments came after German deputy foreign minister Michael Roth lashed out at Brexit over the weekend.

“Brexit is a big shitshow, I say that now very undiplomatically,” Mr Roth told a Social Democratic Party event in Berlin.

He said that “90%” of the UK Cabinet had “no idea how workers think, live, work and behave”.

Politicians “born with silver spoons in their mouths, who went to private schools and elite universities” would not be the ones to suffer the consequences of Brexit, he said.

Responding to Mr Roth’s comments, Mrs May’s official spokesman said: “He answered his own question with the ‘undiplomatic’ comment.

“It is important that we get on with delivering on the verdict of the referendum for the British people. That’s what the Prime Minister is focused on.”

Public opinion of Government’s Brexit negotiations
(PA Graphics)

In an interview with the BBC, Tory chief whip Julian Smith said that the Parliamentary arithmetic means a “softer type of Brexit” is inevitable.

But the Prime Minister has set her face firmly against a customs union, warning it runs counter to the Conservatives’ election manifesto and would inhibit Britain’s ability to strike trade deals around the world.

If she were to give way, she would provoke a furious reaction from Brexiteers, with International Development Secretary Penny Mordaunt and Transport Secretary Chris Grayling among the ministers reportedly ready to resign.

Chief Secretary to the Treasury Liz Truss told BBC Radio 4’s Today programme: “It’s not clear to me that going softer is the way to command support.”

She added: “If you look at the parliamentary arithmetic now, it’s not clear that something like a customs union actually commands support.”

Ms Truss said: “I think that we are well prepared for no deal. I don’t have any fear of no deal.”

And prominent Brexiteer Jacob Rees-Mogg told LBC he was worried that Mrs May was “more concerned to avoid a no-deal Brexit than anything else” and might “decide to go for a customs union tacked onto her deal”.

Mr Rees-Mogg said Mrs May’s Withdrawal Agreement might have won MPs’ approval on Friday, when it was rejected by 58 votes, if the alternative had been a general election.

A letter to the Prime Minister signed by 170 Tory MPs demanded Britain leave by May 22 at the latest “without or without a deal”.

Brexit
Justice Secretary David Gauke has warned Theresa May not to ignore the will of Parliament (Dominic Lipinski/PA)

In a sign of her waning authority, it was written by Brexit Minister Chris Heaton-Harris, according to The Times.

Meanwhile, Jeremy Corbyn sought to keep up the pressure, hinting that Labour could table a fresh vote of no confidence in the Government in a bid to force a general election.

“We’re ready for a general election, whenever it comes,” he told the Daily Mirror.

European Commission president Jean-Claude Juncker said it was time for MPs to make clear what they want.

“A sphinx is an open book in direct comparison with the British Parliament,” Mr Juncker said in a speech in Germany.

He added: “We must get the sphinx to talk now. Enough of the long silence.”