Boris Johnson's future as Prime Minister will be decided by Tory MPs this evening, as he faces a confidence vote.
The secret ballot will take place between 6pm and 8pm on Monday.
If half of MPs vote that they do not hold confidence in Mr Johnson’s leadership, then he will be ousted.
But, as the rules currently stand, if Mr Johnson wins a confidence vote, he cannot be challenged again for 12 months.
The vote was triggered after 54 Tory MPs submitted letters of no confidence to the party's 1922 Committee.
Sir Graham Brady, chairman of the 1922 Committee, said in a statement: “The threshold of 15% of the parliamentary party seeking a vote of confidence in the leader of the Conservative Party has been exceeded.
“In accordance with the rules, a ballot will be held between 1800 and 2000 TODAY MONDAY 6th JUNE — details to be confirmed.
“The votes will be counted immediately afterwards. An announcement will be made at a time to be advised. Arrangements for the announcement will be released later today.”
How will the Boris Johnson confidence vote work?
A ballot box will be placed in a room accessible to all Tory MPs.
Between 6pm and 8pm this evening, all Conservative MPs will be able to cast their vote in the secret ballot.
No pictures will be allowed to be taken inside the room in an attempt to stop party whips from demanding evidence that MPs have supported the Prime Minister.
At 8pm voting will stop and the votes will be counted.
During the last vote of no confidence against Theresa May in 2018, Sir Graham Brady gathered MPs and journalists together to announce the result of the vote.
He will announce whether or not the Conservative party has confidence in Boris Johnson, and reveal the number of votes on each side.
If the result favours Johnson, he will not be able to have another vote held against him for a year, in line with current 1922 Committee rules.
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