BRUSSELS will have to accept Theresa May’s Chequers Plan on Brexit as Britain’s “final offer” or see the UK crash out of the European Union without a deal, Andrea Leadsom has insisted.

The warning from the Commons Leader came as her Cabinet colleague Dominic Raab, the new Brexit Secretary, held his first meeting in the Belgian capital with Michel Barnier, making clear he was “looking forward to intensifying, heating up the negotiations and making sure we are in the best position to get the best deal".

The EU’s chief negotiator, who was due to have dinner with his new counterpart, noted: “On the withdrawal agreement, it is a matter of urgency to agree a legally operative backstop for Ireland and Northern Ireland. We need an all-weather insurance policy."

In an interview with The House magazine, Mrs Leadsom claimed the EU had not taken the UK seriously in terms of the future agreement.

“What this[Chequers] deal does is it says to them: 'Right, now we can have a free trading area where there won't be the need for border checks and controls.'”

She went on: “It needs to take this seriously or we are heading for no deal. The message to the EU has to be: ‘This is the final offer.’”

The Commons Leader made clear the UK was “ramping up” its no-deal preparations and a failure to accept the Chequers Plan would mean “that's where we will be heading and they will have forced us to do that”.

Asked if no deal would be a disaster for Britain, Ms Leadsom replied: "It would not be the optimal solution, obviously; it's definitely less than ideal. The UK would survive and thrive very well in all circumstances."

Meanwhile in the same magazine, Jeremy Hunt, the new Foreign Secretary, claimed the compromise deal, over which his predecessor Boris Johnson resigned, would be the “key to unlocking” the negotiations with Brussels

Declaring Mrs May’s plan was “absolutely alive,” he insisted it was, in fact, the “only way we can square the circle” between the EU’s red lines on protecting the four pillars of the single market and the UK’s in taking back control of its money, borders and laws.

In other developments:

*Labour’s Hilary Benn, who chairs the Commons Brexit Committee, claimed if Britain was on course for a no deal, then MPs would not allow that to happen but step in and "take control" of the Brexit process – although he did not elaborate how;

*Jim Harra, a senior official at HM Revenue and Customs, told a Lords committee that applying the Government’s proposed Facilitated Customs Arrangement could add £700 million a year to business costs – a fraction of the £20 billion a year a colleague suggested was the price-tag for Whitehall’s original “max-fac” option;

*John Manzoni, the Civil Service chief, told MPs: "We will be ready for a no deal Brexit. Not everything will be perfect";

*the European Commission urged the EU27 to “step up” preparations for a possible no-deal Brexit, warning of the possibility of long queues at borders and disruption at airports;

*Esther McVey, the Work and Pensions Secretary, failed publicly to say she had confidence in the Chequers Plan, preferring to say she had confidence the PM would “deliver the Brexit people voted for” and

*her partner, Yorkshire MP Philip Davies, became the third Tory to confirm he had submitted a letter of no confidence in Mrs May, saying he had lost trust in her ability to deliver Brexit.