Former work and pensions secretary Esther McVey has announced that she will stand for the Conservative leadership when Theresa May steps down.

Ms McVey, who quit the Cabinet in November in protest at Mrs May’s Brexit deal, became the third Tory openly to declare her ambition to be Prime Minister, after Andrea Leadsom and Rory Stewart.

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The staunchly Leave-backing MP’s announcement came as Justice Secretary David Gauke issued a call for the party to steer away from populism, in what was seen as a bid to prevent a lurch to the right after Mrs May’s departure.

Asked whether she will stand in the battle to replace Mrs May, Ms McVey told TalkRadio: “I have always said quite clearly if I got enough support from my colleagues, yes I would.

“Now people have come forward and I have got that support, so I will be going forward.”

The Tatton MP said the Conservative Party needed a leader who “believes in Brexit”, and had “belief in the opportunities” it could bring.

Ms McVey said that Mrs May’s departure should be handled in a “dignified and graceful” way.

“We all know Theresa May is dutiful,” she said. “She has worked for public service for many years.”

As rivals limber up for the succession battle, Mr Gauke warned that populist policies would leave Britain poorer and more divided and put the Union at risk.

GaukeJustice Secretary David Gauke warned Conservatives against taking a populist route (Dominic Lipinski/PA)

Appealing to the party to stand by the banner of One Nation Conservatism, the Justice Secretary used a speech to the Onward thinktank to call for for a politics which is civil, open-minded and forward-looking.

Although he is not often mentioned in lists of potential successors to Mrs May, Mr Gauke’s comments will be seen as an intervention in the leadership contest to come after the PM steps down, as she has said she will once the first phase of Brexit is complete.

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One of the Cabinet’s most prominent opponents of a no-deal Brexit, Mr Gauke’s speech is likely to be interpreted as a caution to the party not to choose a leader from among advocates of the hardest forms of EU withdrawal, like Boris Johnson or Dominic Raab.

Speaking to BBC Radio 4’s Today programme ahead of his speech, he urged Tory MPs to back Mrs May, saying that removing her as PM would not change the parliamentary arithmetic on Brexit.

“I think it would be a mistake to have a change of leadership at this point,” said Mr Gauke.

When the Conservatives choose their next leader, the focus should be on “what is the role of the UK in a post-Brexit world and who is the best candidate to defeat Jeremy Corbyn”, he added.

In his speech, Mr Gauke said the arguments of some Brexiteers has been “characterised by wishful thinking” which has “not survived the collision with reality”.

Voters’ anger over the failure to deliver Brexit on time has been fuelled by some Leave supporters’ over-simplification of the difficulties involved, he said.

And he argued that the Government must put the economy at the heart of its Brexit strategy, discouraging a “culture war” over relations with Europe and ensuring that the UK maintains “strong trading relationships with our biggest trading partner”.

In a challenge to populists’ claim to be the heirs of the most successful Tory leader of modern times, he insisted that Margaret Thatcher led her party and her country by confronting populism, not embracing it.

Mr Gauke warned that the growth of populism has driven a coarsening of political debate, with language becoming more extreme and civility dismissed as weakness.

But he said that on the key political arguments, populists are “just plain wrong”.

Populist politics would “make us a poorer and a more divided nation” and fail to satisfy voters who feel disillusioned by the current system, he said.

It involves an attack on the very institutions which underpin the UK’s political stability and threatens to undermine the United Kingdom itself by manifesting itself in the guise of English nationalism, warned Mr Gauke.

“Conservatism should be broad, not narrow; open, not closed; forward-looking, not yearning for a mythical past,” he said.

“It should be based on an appeal to the common-sense, pragmatic instincts of the majority. We should seek to unite, not divide. One Nation Conservatism.

“Pragmatic, practical, reasonable but determined. That is the character of the British people. That is the character of Conservatism at its best.”

Calling for a de-escalation of the “culture wars” which have raged since the 2016 Brexit referendum, Mr Gauke said the Tories should promote civil debate and mainstream politics.

And he said the party must be ready to be open with voters about the need for trade-offs and the fact that “an easy, simple answer is often the wrong one”.

Mr Gauke warned against “sneering” at those rallying behind populist calls for a swift and “clean” break from Europe.

He said Conservatives should not follow failed US presidential candidate Hillary Clinton in dismissing those concerned about rapid changes to the national culture and economy as “deplorables”.

Instead, the party’s platform must be seen to benefit society as a whole and offer an “aspirational and optimistic” message to those seeking opportunity and improved living standards.