July 5

• Former finance minister Rishi Sunak and health secretary Sajid Javid quit Mr Boris Johnson’s government, helping to trigger a rebellion that brings down their boss.
• It also triggers a race within the Conservative Party to look for Mr Johnson’s replacement.

July 13-20

• Mr Sunak and Ms Liz Truss reach the last round of the contest after a series of votes by Tory MPs reduced the field of contenders from eight to two.
• Mr Sunak, who was in the lead in every round of voting, ends with 137 votes in the fifth and final ballot.
• Ms Truss overtakes another contender, Ms Penny Mordaunt, only in the final round to secure second place with 113 votes.

Sept 5

Members of the Conservative Party vote by post in the final run-off. Ms Truss wins 57 per cent of the votes compared with 43 per cent for Mr Sunak.

Oct 20

Mr Sunak quickly emerges as the most likely front runner hours after Ms Truss resigns as Conservative Party leader and says she will step down as prime minister by Oct 28.

Oct 21

Several former Cabinet ministers back Mr Sunak. By the evening, the Sunak camp claims their candidate has the support of more than 100 MPs.

Oct 22

• Mr Sunak’s team claims 120 votes by the end of the day.
• Ms Mordaunt officially joins the race.
• Mr Johnson flies home from Dominican Republic to join the race.

Oct 23

• Mr Sunak confirms his candidacy. He lines up at least 155 votes by late afternoon, according to a tally by the BBC, more than double the number pledged to Mr Johnson.
• Later in the evening, Mr Johnson pulls out of the leadership race, leaving Mr Sunak the clear front runner.

Oct 24

• Ms Mordaunt withdraws from the race.
• Mr Sunak is elected Conservative leader and will become the next prime minister. He will be Britain’s third PM in less than two months and its first non-white leader.