Who is Prime Minister now - and when are they out? Here's where we stand on the timetable for the all-change in Downing Street
Theresa May will be Prime Minister by Wednesday night after David Cameron quit.It will bring new drama to a month of the highest drama British politics has seen in decades.
Labour was expecting to mount a long summer leadership contest alongside a Tory battle for Number 10.
But Mrs May's right-wing rival Andrea Leadsom dropped out - shortening the nine-week Tory leadership race to just a few days.
Here's where we stand on the timetable for putting a new Prime Minister in Downing Street.
Live: Theresa May to be Prime Minister 'by Wednesday evening' says David Cameron
Live: Theresa May to be Prime Minister 'by Wednesday evening' says David Cameron
When will Theresa May be Prime Minister?
David Cameron has confirmed he is bowing out on Wednesday after a final Prime Minister's Questions.He will take a valedictory session with some gentle ribbing after chairing his final Cabinet meeting on Tuesday.
He told journalists: "After that I expect to go to the palace and offer my resignation.
"So we will have a new Prime Minister in that building behind me by Wednesday evening."
What did David Cameron say?
The outgoing Prime Minister said in a quick statement: "I'm delighted we're not going to have a prolonged Conservative leadership campaign."
He added: " Andrea Leadsom made the right decision to step aside."
And confirming a formal announcement by the party that hasn't yet been made, he said Mrs May "will be the next Prime Minister".
Was Theresa May even confirmed as PM yet?
Technically no, but it was a question of when not if.Graham Brady, chairman of the 1922 Committee of Tory backbenchers, said the decision had to be run past the 22-strong party board.
But asked if there was a chance the contest would be re-opened, he said: "None whatsoever. We have a single candidate.
"The position is now we need formal confirmation of the new leader of the party."