Housing minister Kit Malthouse has withdrawn from the Tory leadership race as the party changed its rules to make it harder for outsiders to stand.
The field of candidates is now down to 11 after James Cleverly also pulled out earlier today.
Malthouse said he was a realist and acknowledged there was an appetite for this contest to be over quickly.
Cleverly, who was elected in 2015, said his fellow MPs were not comfortable with the idea of picking a relatively new colleague.
The executive of the backbench 1922 Committee and the party board met to decide the rules for the contest which will see the new leader finally elected in the week beginning July 22.
In order to deal with the crowded competition, candidates now need to secure support from eight MPs rather than the two required under the system used in 2016.
To stay in the contest, candidates will then need to win at least 16 votes in the first ballot and 32 in the second round in order to speed up the process of whittling them down to a final two.
If the ballot thresholds are met by all candidates, then the candidate with the lowest number of votes will be eliminated.
The first ballot of MPs will take place on June 13, with further votes scheduled on June 18, 19 and 20.
The winner – and the next prime minister – will be decided by Tory members from the two candidates remaining at the end of the process.
The process will begin with a call for candidates at 5pm on Friday, after Theresa May formally quits as Tory leader.
Nominations will be received from 10am on Monday, June 10 and will close at 5pm that day.
Once the parliamentary votes have been completed, the first membership hustings is planned for June 22, with the whole process due to end in the week beginning July 22.
Boris Johnsons former campaign manager Ben Wallace said he hasnt decided yet whether to back him again in his latest party leadership bid/
While Brexiteer Liam Fox announced he is backing Jeremy Hunt, who recently described a no-deal Brexit as political suicide.
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