A meeting of the Conservative Party Board set the formal timeline for the leadership contest, which opens on Wednesday and closes on Thursday before a shortlist is drawn up.
A Conservative Party spokesperson said: “The Party Board welcomes the recommendation of the Executive of the 1922 Committee with regards to the Parliamentary timetable for the selection of the new leader of the Conservative Party.
“The leadership election should take place as speedily as practical considerations allow. In order to ensure there is full participation by the membership, the Board recommends that the date of the declaration of the leader is 9 September.”
Known for his unconventional political style, the 52-year-old journalist-turned-politician Johnson had led the Brexit camp in the June 23 referendum, falling out with his mentor and party leader Cameron who aggressively campaigned for Britain to stay in the 28-member European Union.
Other candidates emerging in the fray include United Kingdom’s longest-serving home secretaries in history, Theresa May, who turns 60 later this year and has reportedly gathered strong support, followed by UK health secretary Jeremy Hunt.
May also narrowly beat Johnson as the politician the country thinks would make the best prime minister, according to a YouGov poll on Tuesday.
May was backed by 19 per cent of the public, compared to 18 per cent who backed Johnson.
A number of other Conservative MPs were also scrambling to build up support for themselves as potential candidates to replace Cameron, who was elected party’s leader in 2005.
The 54-year-old former defence secretary, Liam Fox, who finished a close third during the 2005 contest for Tory party leadership, is also expected to throw his hat in the ring for a second time.
Pakistani-origin business minister, Sajid Javid, is said to be considering a bid too, while UK work and pensions secretary Stephen Crabb has officially declared his plans to enter the Tory leadership race.
However, UK Chancellor George Osborne has ruled out his candidature.
‘I was full-throttled in arguing for remaining in the EU and because half my party wanted to leave the EU I don’t think I can be the person to bring this party together, at the moment,’ he told BBC on Tuesday.
He said the right candidate to lead the country was the person who is ‘able to articulate the clearest, crispest version of what relationship we are seeking’ with the EU.
The Conservative party’s Committee had on Monday announced a leadership timetable, which will see two short-listed candidates go head to head to be elected new leader.
Chair of the executive body, Graham Brady, said: “I think the view of the party is that both we as Conservatives and the country more generally, really want certainty, we would like some resolution, and we think it would be a good thing to conclude this process as soon as we practicably can.
“That ought to mean that we would have a new prime minister before the House of Commons returns for its September sitting.”
Whoever next ends up in No 10 Downing Street will begin extracting the UK from the economic bloc as Cameron said it will be the new prime minister who will take the negotiations forward.
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