David Cameron is definitely the prime minister.
For at least some more of this week.
After Andrea Leadsom sensationally quit the race for leadership of the Conservative party on Monday, Theresa May is almost the new prime minister.
David Cameron has announced that he will take his final PMQs on Wednesday, then head to the palace to offer his resignation to the Queen. Theresa May is therefore expected to be installed as prime minister by Wednesday evening.
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