There may not yet be an official leadership contest, but senior Tories are wasting no time in setting out their desire to replace Theresa May.

– When will Theresa May quit?

The Prime Minister’s fate will be sealed by a vote on her Brexit deal in the form of the Withdrawal Agreement Bill in the week beginning June 3.

She will set out the timetable for the leadership contest to replace her after the result of the vote on the deal, with defeat likely to lead to a swift exit from Number 10.

Brexit
Theresa May will wave goodbye to Number 10, with the timetable for her departure due to be set out in early June (Matt Dunham/PA)

– Who is in the race?

Who isn’t? It looks likely to be a crowded field, with former foreign secretary Boris Johnson the bookmakers’ favourite.

His closest rivals on the Eurosceptic wing of the party are former Brexit secretary Dominic Raab and Environment Secretary Michael Gove, who scuppered Mr Johnson’s leadership bid in 2016.

Most senior ministers are refusing to confirm they will stand until after Mrs May announces her departure date, but International Development Secretary Rory Stewart has confirmed his ambitions for the top job and said he expects at least six more of his colleagues around the Cabinet table to launch leadership bids.

Foreign Secretary Jeremy Hunt, Home Secretary Sajid Javid, Health Secretary Matt Hancock, Treasury Chief Secretary Liz Truss and Commons Leader Andrea Leadsom are all thought to be considering a run at the leadership.

– What should we look out for?

Increased social media activity, staged appearances with family members, quirky photo shoots, speeches straying far beyond ministerial portfolios – if a Tory MP is doing any of these things, it’s likely they have at least one eye on Number 10.

– What are the various factions?

Former work and pensions secretary Esther McVey, another of the leadership hopefuls, was at the launch of the new Blue Collar Conservatism group aimed at attracting working-class voters.

The centrist One Nation Conservatives group launched on Monday night, with support from Work and Pensions Secretary Amber Rudd and ex-cabinet minister Nicky Morgan.

Mr Johnson wasted no time in seeking to win the backing of the group, claiming that its values have “never been more important”.

The European Research Group is the influential Brexiteer wing of the Tory Party, led by Jacob Rees-Mogg. He has indicated his support for Mr Johnson, but the group is likely to split between various Eurosceptic candidates.

– What about Brexit?

The pressure to win over Eurosceptic Tory members could force candidates to take a hardline view, something Chancellor Philip Hammond is warning against.

In a speech to business leaders he cautioned against “right-wing populism” and said that “to advocate for no deal is to hijack the result of the referendum, and, in doing so, knowingly to inflict damage on our economy and our living standards”.