Theresa May has lost a vote of confidence in her leadership of the Conservative Party. A full election for the role of leader must now be held, in which she cannot stand.
Under the rules of the Tory party, MPs will whittle down the field of candidates to a field of just two, who will then face election by ordinary party members. This makes it the first time in the history of the United Kingdom that a sitting Prime Minister will have been chosen in this way.
Parliamentarians are expected to have a wide field to choose from. Sitting Cabinet ministers Sajid Javid, Jeremy Hunt, and Amber Rudd are all tipped to stand, as well as Boris Johnson, Dominic Raab and Esther McVey, all currently on the backbenches.