Labour leadership challenge looms after Starmer's election setback

Labour’s post-election headache has hardened into a direct challenge to Keir Starmer’s authority, with Catherine West threatening to force a leadership contest unless the Cabinet moves against him by Monday. Downing Street has tried to play down the move, but it has already put Westminster on notice that the question is no longer just about bad results, but about whether Starmer can still command his party.

The pressure built after Labour suffered heavy losses in the 2026 local elections and in devolved votes in Scotland and Wales. Reform UK, led by Nigel Farage, won more than 1,000 council seats in England, while Labour’s performance was described as among the worst for any governing party since 1995. The scale of the test was unusually broad, covering 136 local councils in England as well as the Scottish and Welsh parliaments. Starmer said he was “not going to walk away” and admitted Labour had made “unnecessary mistakes.”

The mechanics of any challenge are steep. Labour rules require a challenger to be an MP and to win nominations from 20% of Labour MPs, a threshold raised from 10% in 2021. With 403 Labour MPs, that means 81 backers. If a contest is triggered, the incumbent leader automatically appears on the ballot paper. If Labour’s leader is also prime minister and the leadership becomes vacant, the Cabinet, in consultation with the National Executive Committee, would appoint one of its members as leader until a ballot could be organised.

That is why West’s move matters beyond the numbers. She said on 9 May that she would seek to trigger a contest unless the Cabinet moved against Starmer, and that she would ask colleagues in the Parliamentary Labour Party to back her if no other hopeful emerged. The gambit caught officials off guard and opened speculation about whether other senior figures, including Angela Rayner and Wes Streeting, could be pulled into the race.

Starmer has responded by bringing in Gordon Brown and Harriet Harman as special envoys, a signal that the leadership is trying to steady the party after the rout. But the real test is still ahead: whether MPs begin to organise, whether senior figures stop defending the leadership, and whether the party machine starts to wobble. Starmer won a landslide in July 2024, but after one bruising set of results, the question is whether his authority is being tested or quietly unraveling.