Starmer confirmed he will remain in place as prime minister until a new Labour Party leader has been selected.

The dramatic exit comes less than two years after Starmer won a landslide election victory.

His government took power on an explicit promise to end Britain's chaotic politics, a goal cut short by deep internal party divisions.

The political threat to Starmer has been building for months. However, the pressure increased last week when Manchester mayor Andy Burnham decisively won an election to return as a lawmaker in parliament.

Burnham has officially confirmed he is running for leader to succeed Starmer.

In a major boost to the mayor's campaign, the man considered his main rival for the role, Wes Streeting, has ruled himself out and come out in support of Burnham.