The Mirror understands Cabinet ministers have approached Labour backbenchers with Leave seats to attempt to win them around if there’s a vote in the Commons.
It comes despite the EU pouring scorn on Mr Johnson’s new Brexit plans – raising the threat they will never actually make it to a Parliamentary vote.
The EU’s chief Brexit negotiator Michel Barnier said: “If they do not change, I do not believe, on the basis of the mandate I have been given by the EU27, that we can advance.”
It’s thought senior figures hope they can show Brussels there is support for the plan by staging a showdown in Parliament.
There is speculation the PM could offer MPs a non-binding vote on his plans before a crucial Brussels summit on October 17 – to show the level of support, or otherwise, among MPs.
Senior Labour insiders believe around a dozen MPs could be persuaded to back a version of Mr Johnson’s deal if one is agreed by the EU against the odds.
Others think the figure is higher – as many as 20 – although some of those have concerns over the PM’s plans for the future relationship with the EU, which they fear could lead to rights and environmental standards being ripped up.
Just five Labour MPs voted for Mrs May’s deal last time – Caroline Flint, Rosie Cooper, Jim Fitzpatrick, Kevin Barron and John Mann.
The PM himself has put little effort into winning over Labour MPs and some of those who have spoken with ministers claimed there had been no indication that any concessions were on offer.
Labour MP Lisa Nandy said up to 40 Labour MPs could vote for a Brexit deal, but that she would not support Mr Johnson’s current proposals herself.
She told Sky News: “I think there are a lot of Labour MPs, there are about 40 still who have been working cross-party for the last three years trying to find a way to achieve a deal and there are still discussions going on.”
She added that “some limited conversations” with Government ministers had taken place.
But she added: “It’s deeply frustrating that for all of this talk about getting Brexit done, he doesn’t seem to be serious at all about trying to agree a cross-party deal and move us forwards”.
Brexit Secretary Stephen Barclay today confirmed talks have been taking place with MPs from across the Commons.
One MP approached by a “rude and undiplomatic” Cabinet minister told the Mirror that he experienced “poor judgement and failure to actually listen”.
Others have highlighted the “stark contrast” with Theresa May’s approach.
Despite the approaches to MPs, Boris Johnson has also ramped up his No Deal rhetoric after EU leaders all but dismissed his new Brexit plan.
The Prime Minister insisted today that the UK would leave the EU on October 31 despite MPs legislating to stop it.
“The only question is whether Brussels cheerily waves us off with a mutually agreeable deal, or whether we will be forced to head off on our own,” he said.
“We are leaving in 25 days. We can do it with a deal if the EU is willing. But they should be under no illusions or misapprehensions.
“There will be no more dither or delay. On 31 October we are going to get Brexit done.”
But his tough rhetoric immediately prompted accusations that he was simply trying to blame any delay on Brussels after breaking his “do or die” pledge to leave on time.
EU chiefs claimed that the PM had not made any serious attempts to get a deal.
Brussels chief negotiator Michel Barnier said: “These negotiations have been lose-lose since the beginning. We are ready for a no-deal, even if we do not want it.”
Brussels chiefs are waiting to hear whether Mr Johnson was prepared to compromise further on his Brexit plans.
If not the plans – which involve “two borders” in Northern Ireland to replace the so-called ‘backstop’ clause – are expected to be rejected formally in the next few days.
Latvian PM Krišjānis Kariņš claimed it was now “a bit of a long shot” to get a deal done before October 31.
He warned the UK not to offer a “take it or leave it” offer.
Meanwhile, the Attorney General has reportedly threatened “resignations” if Boris Johnson refuses to write a letter asking the EU to delay Brexit.
Geoffrey Cox sounded the alarm amid a furious row over whether the Prime Minister will defy the law to ram through a no-deal departure on October 31.
Court papers on Friday finally confirmed he would comply with the ‘Benn Act’, and send a delay letter to 27 EU leaders.
Yet the PM then personally intervened on Twitter to say: “New deal or no deal – but no delay.”
Cabinet ministers Steve Barclay and Robert Jenrick on Sunday yet again refused to confirm the PM will send the crucial letter.
Shadow Attorney General Shami Chakrabarti today said the PM “speaks with forked tongue” by saying two different things at the same time.
She told the BBC: “He seems to have a very casual relationship with the law. He seems to think he’s above the law as the Supreme Court showed us a few weeks ago.
“He is not. No one is above the law, even a British Prime Minister.”