Seven Tory Cabinet ministers will today launch a bid to prevent Boris Johnson from leading Britain out of the EU without a deal if he becomes the next leader of the party.

In a significant intervention, the 60-strong 'One Nation Caucus' of Conservative MPs will publish a 'declaration of values' rejecting 'narrow nationalism'.

The group last night said it aimed to 'shift the Conservative Party towards the centre'.

Sources close to Boris Johnson (pictured) said yesterday he would not form an electoral pact with Nigel Farage's Brexit Party which some Eurosceptics are demanding. One ally said: 'Of course he won't do a deal with Farage – he's the man to beat Farage'

Sources confirmed it would hold hustings during the impending leadership contest and would 'work to stop any leadership candidate who endorses a 'Nigel Farage No-Deal Brexit'.

The stance is a direct warning to Mr Johnson and other Tory leadership candidates flirting with a No Deal Brexit.

The new group was founded by Work and Pensions Secretary Amber Rudd and former education secretary Nicky Morgan with the backing of former prime minister Sir John Major.

Including Miss Rudd, it counts at least seven Cabinet ministers as members: David Gauke, Greg Clark, Rory Stewart, David Mundell, Claire Perry and Caroline Nokes.

The new group was founded by Work and Pensions Secretary Amber Rudd (pictured) and former education secretary Nicky Morgan with the backing of former prime minister Sir John Major

Cabinet ministers Greg Clark (left), Claire Perry (centre) and David Gauke (right) are members of the group

Other Cabinet ministers Caroline Nokes (left) and David Mundell (right) are also in the group

An eighth senior minister, Chancellor Philip Hammond, will go public tomorrow with his concerns about a Tory lurch towards populism, describing it as 'the politics of easy answers'.

Mr Stewart, the new International Development Secretary, yesterday said he would find it 'very difficult' to stay in a Conservative Party led by someone pursuing a No Deal strategy.

He told the BBC's Andrew Marr Show that No Deal would be 'damaging and unnecessary' and said the UK would eventually have to do a trade deal with the EU anyway.

Rory Stewart (pictured), the new International Development Secretary, yesterday said he would find it 'very difficult' to stay in a Conservative Party led by someone pursuing a No Deal strategy

He added: 'If you go down the path of No Deal Brexit you're going to lose 4 million Remain voters who voted for the Conservatives last time, so you won't win an election, and No Deal Brexit is a vote for Jeremy Corbyn.'

Mr Stewart, who has announced he will stand in the Tory leadership contest, said he would legislate to prevent No Deal if he became prime minister.

Mr Johnson, the runaway favourite to be the next Tory leader, has made it clear he is willing to pursue a No Deal Brexit if the EU refuses to make concessions.

Sources close to Mr Johnson yesterday said he would not form an electoral pact with Nigel Farage's Brexit Party which some Eurosceptics are demanding.

One ally said: 'Of course he won't do a deal with Farage – he's the man to beat Farage.'

Several other leadership candidates, including Dominic Raab and Andrea Leadsom, are also expected to endorse a No Deal strategy, which is overwhelmingly backed by Conservative Party members, who have the final say in the contest to choose Britain's next prime minister.

Sources confirmed it would hold hustings during the impending leadership contest and would 'work to stop any leadership candidate who endorses a 'Nigel Farage No-Deal Brexit'. Mr Farage is pictured above at a rally for the Brexit Party on Sunday

Brexit Secretary Steve Barclay warned that the UK would have to ramp up No Deal preparations if MPs vote down Theresa May's deal for a fourth time.

Mr Barclay, who is considering his own bid to succeed Mrs May, told Sky News it was time for MPs to 'face the facts' that they had only three options – backing Mrs May's deal, leaving without a deal at the end of October or cancelling Brexit, which would be 'disastrous' for democracy.

He added: 'If Parliament won't back a deal then it needs to confront that reality and I do think in that instance we need to bring forward our preparations to mitigate No Deal.

'There is no guarantee that the EU 27 will grant an extension. That is a non-UK decision on the October 31 so that would be a matter for the EU, so we do need to prepare for No Deal and ensure that we use the time we have to mitigate any disruption as best we can.'

Mr Hammond will use a speech to the CBI tomorrow night to issue a warning on the dangers of populism. And he will warn that a No Deal Brexit would leave any new leader unable to pay for expensive campaign pledges on other issues.

Urging the next leader not to abandon fiscal discipline, he will warn against them going on a 'spending spree', saying that 'borrowing today has cost tomorrow'.

The One Nation Caucus will formally launch its 'declaration of values' tonight, describing its members as 'patriotic Conservatives who reject narrow nationalism'.

Key aims include ensuring the UK remains 'a leader on the world stage through our aid, trade and security commitments to tackle global challenges as a global citizen'.

Hopefuls STILL playing happy families

A picture tells a thousand words in politics – so Tory leadership hopefuls were out in force at the weekend, cameras at the ready, to document their 'normal' lives.

Commons Leader Andrea Leadsom went for a family walk in Harrogate, North Yorkshire, on Saturday with her husband Ben, daughter Charlotte and son Freddie, posting a selfie of the ramble on Instagram.

Meanwhile, Boris Johnson and his girlfriend Carrie Symonds were spotted bird-watching at Bempton Cliffs nature reserve near Bridlington, in the East Riding of Yorkshire, before tucking into a £7 fish supper from a local chippy.

Selfie: Mrs Leadsom in a group with Ben, Charlotte (at back) and Freddie. The family went for a family walk in Harrogate, North Yorkshire, on Saturday

Boris Johnson and his girlfriend Carrie Symonds were spotted bird-watching at Bempton Cliffs nature reserve near Bridlington, in the East Riding of Yorkshire, before tucking into a £7 fish supper from a local chippy

Pub tour: Miss McVey, with fiance Philip Davies, detailed her policies

The photos follow recent snaps of Jeremy Hunt with his wife and Dominic Raab in his kitchen.

In contrast with her rivals' outdoorsy approach, Esther McVey upped the ante by spelling out some of her policies, including a call to take billions of pounds from the aid budget to spend on domestic priorities in a 'blue collar' pitch for votes.

The former cabinet minister, who will formally launch her bid for the leadership this week, wants annual aid spending of more than £14.5billion to be cut to the 2010 levels of less than £9billion.

Her pitch also involves more funding for police and schools and axing HS2.

She will set out her stall today at the launch of a new Blue Collar Conservatism group that will concentrate on a domestic policy agenda to appeal to 'ordinary working people'.

Miss McVey, who revealed her engagement to MP Philip Davies last month in the Mail, then starts a pub tour to meet voters.