Stephen Crabb will run for Conservative party leader alongside business secretary Sajid Javid in an effort to overcome the "Bullingdon Club" image of David Cameron's premiership.

The recently appointed work and pensions secretary, who is an evangelical Christian, grew up with his single mum on a council estate in west Wales. Javid is the son of a bus driver from Bristol. The Tory leadership contest was triggered after Cameron announced he would resign in the wake of the vote to leave the European Union, which he campaigned against.

The 43-year-old former Welsh secretary announced his candidacy in an email to Tory MPs on Tuesday, according to POLITICO.

Javid will run as his number two, Christian Today can confirm, and would become Chancellor should Crabb win the race. The "blue-collar dream team" will be supported by MPs Simon Hoare, Maria Caulfield and Craig Williams.

Although the pair mark a stark contrast to old-Etonian Boris Johnson, Crabb and Javid both campaigned for remain which is likely to harm their chances.

The declaration comes after Chancellor George Osborne ruled himself out of the race. The long-term ally of Cameron had been tipped to succeed him as Prime Minister. But after defeat in the EU referendum and plummeting ratings among grassroot Tory activists, Osborne announced in the Times he would not run for the leadership.

Boris Johnson and Theresa May are expected to announce their bid for leadership this week as the Conservative party headed for a summer in turmoil.

Home secretary May is tipped to be favourite for the role after a poll in the Times put her ahead of Johnson with 34 per cent of Tory voters' support to Johnson's 24 per cent. This compared to a separate poll in April that place Johnson on 36 per cent and May on 14 per cent.

The survey announced on Tuesday puts a clear gap between May and Johnson as the clear frontrunners. Gove was a distant third on five per cent with Javid on three per cent and Crabb on two per cent.

Nicky Morgan, another Christian in the cabinet, is poised to announce her bid for leader after she lauded her credentials in an article for the Tory blog site Conservative Home.

Others said to be considering a leadership bid are health secretary Jeremy Hunt, energy minister Andrea Leadsom and former defence secretary Liam Fox.

Speaking on Monday, Crabb said: "We need stability. We need direction.

"And what I want to see in the next few days is a candidate emerge who understands the enormity of the situation that we're in and who has got a clear plan, a clear plan to deliver on the expectations of the 17 million people who voted for Britain to come out of Europe last week, a clear plan for putting together a team who can lead a tough negotiation in Brussels; [and] a plan for holding this United Kingdom together.

"And that means, yes, going and working with [Scotland's SNP First Minister] Nicola Sturgeon and holding onto the union. Because this isn't just about party unity now; it's about national unity."

Nominations for the next Tory leader, and therefore next Prime Minister, open on Wednesday and close at noon on Thursday. According to Conservative party procedure, if more than two candidates are put forward, Tory MPs will hold an election to reduce the field to a straight choice of two options. That decision will then be handed to the Conservative party leadership with a result expected to be announced by September 2.