- Under the obscure system, revealed on Tuesday evening, Conservative MPs will whittle down 11 candidates over several weeks before selecting two to be put to a full vote by party members.
- Around 160,000 Conservative members will be allowed to decide Britain's next prime minister out of an electorate of 47 million people.
- The final result will be revealed at the end of July.
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LONDON Theresa May's resignation as Conservative party leader has fired the starting gun on the process of choosing her successor as leader and prime minister.
Under Britain's parliamentary system, the new prime minister will be chosen by around 140,000 members of the governing Conservative party, without the involvement of Britain's 47 million voters.
The first hustings in the contest took place on Tuesday night at a closed-door event inside parliament with no reporters allowed inside.
Under the rules of the contest, revealed on Tuesday evening, the whole race will be wrapped up by the end of July.
Eleven Conservative MPs are currently in the running for the job.
Leading the pack are bookies' favourite Boris Johnson plus Cabinet ministers Michael Gove and Jeremy Hunt.
Here's how the contest will work.
The first hurdle
The official deadline for MPs wanting to enter the leadership contest is 17:00 (BST) on Monday, June 10 .
The rules drawn up on Tuesday require entrants to have the support of a least eight Conservative MPs. If they do not have this much support, they will not be able to enter the leadership contest.
The 1922 Committee came up with this rule in order to quickly eliminate candidates who have virtually no chance of winning from a crowded field. Under previous rules, hopefuls needed the support of just two MPs.
Sam Gyimah the only MP in the running who is offering a new referendum on Brexit said that it was "slightly disappointing" to see the rules changed well after wannabe leaders had launched their bids.
Gymimah is in a handful of runners who are at risk of not having enough support to get over the first hurdle, which also includes former House of Commons leader Andrea Leadsom and Twitter sensation Rory Stewart.
Conservative MPs will hold multiple rounds of secret voting to whittle down the shortlist of candidates.
The first secret ballot will take place on Thursday, June 13 . Candidates will need to secure the support of at least 17 Conservative MPs to get through that's just over five per cent of the Tory party's 313 MPs.
The second will take place on Tuesday, June 18. Candidates will then require the official backing of at least 33 of their Conservative colleagues in the House of Commons in order to progress to the next stage.
If all of the candidates meet these thresholds, then the one with the lowest number of backers will drop out.
This process of secret voting will continue until the list has been whittled down to the final two, with votes scheduled to take place on Wednesday, June 19 and Thursday, June 20.
You should expect plenty of drama during this process.
Candidates will work tirelessly behind the scenes in Westminster to get as much support as possible and will likely offer MPs government jobs in exchange for their backing.
Candidates may also partake in televised debates, with the BBC and Sky hoping to broadcast events.
Conservative members take over
A key point about Conservative leadership contests is that while MPs whittle down the shortlist of candidates, it is the wider party membership will who ultimately vote on the final two and decide who is the new leader.
There are around 124,000 members of the Conservative party, in a country of some 66 million people.
Under the rules agreed on Tuesday, the final two candidates will participate in a number of members hustings across the country, with the first set to take place on Saturday, June 22.
Hustings will continue for nearly a month until the end of July.
A new leader and prime minister is announced
Having grilled the final two candidates in hustings across the country, Conservative party members will then vote on who they want to succeed May as Tory leader and prime minister of the UK.
This is set to happen by the week beginning Monday, July 22.
By the end of next month, the UK will have a new prime minister.
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