The Westminster Desk | Brief

Britain changes Prime Minister on Monday. Here is the exact timetable, and how it was fixed.

The arithmetic

Andy Burnham entered this week with 322 nominations from Labour MPs and added 27 more on Monday, taking him to 349 of the party's 403. Any challenger needs 81 nominations to reach the ballot. With 54 MPs left unpledged, no rival can qualify. The contest ended, in effect, by arithmetic.

The timetable

Sir Keir Starmer announced his resignation on 22 June, after heavy local election losses in May and Mr Burnham's victory in the Makerfield by-election, which returned him to the Commons. As the only qualifying candidate, Mr Burnham is expected to be confirmed as Labour leader at a special party conference on Friday 17 July, and to become Prime Minister on Monday 20 July. He will be the country's seventh Prime Minister in a decade.

The overlaps

The handover lands in a crowded week. Nominations for the Clacton by-election close at 4pm on Friday, hours before the special conference. Polling day in Clacton, 13 August, now falls three and a half weeks into the new premiership, making a by-election the new Prime Minister neither called nor contested his first electoral test. The desk's Clacton tracker follows that contest separately.

What to watch: the special conference on Friday, the handover on Monday, and the first Prime Minister's Questions of the Burnham era.