Outlook Explains | Keir Starmer Won A Historic Majority. So Why Did He Quit in Two Years?

Today, Keir Starmer walked out of 10 Downing Street and announced his resignation as Prime Minister and Leader of the Labour Party formally.

Speaking outside Downing Street, Starmer said he had spoken to His Majesty the King before making the statement, and that he would ask the National Executive Committee of the Labour Party to set out a timetable with nominations for a new leader opening on July 9, with the process completed before Parliament returns in September.

He said he would remain prime minister until the contest is complete. "The question my party is asking now is whether I am best placed to lead us into the next general election. I have heard the answer of my parliamentary party to that question, and I accept that answer with good grace," he noted.

It was not exactly a surprise. Speculations were already there. On top of that US President Donald Trump had announced it on Truth Social the night before Starmer said a word publicly, an intervention the Washington Post described as "extraordinary." But beyond the drama, the real story of how a man who won the largest Labour majority in a generation ended up leaving office in under two years is the question worth asking.

Landslide Masked the Cracks

Starmer led Labour to a sweeping general election victory in July 2024, ending fourteen years of Conservative government. The scale of the win obscured something important — Labour had not won enormous support so much as the Conservatives had catastrophically collapsed.

According to NPR's reporting, Starmer's popularity cratered after the victory. He struggled to deliver promised economic growth, repair tattered public services and ease the cost of living, and was hamstrung by repeated missteps, including his decision to appoint Peter Mandelson as the UK ambassador to the US.

Time Magazine reported that newly released government files showed Starmer had been warned of the "reputational risks" of the Mandelson appointment before making it, given Mandelson's ties to the late convicted sex offender Jeffrey Epstein. Starmer fired Mandelson in September 2025, but the damage was already done.

The May 2026 local elections were the visible breaking point. More than 80 of Starmer's Labour colleagues called on him to leave after disastrous results that saw Labour lose more than 1,100 council seats across England, while Nigel Farage's Reform UK won more than 1,450.

The Cabinet Revolt

What made Starmer's situation truly impossible was not just the polls but the people around him walking out. Former Health Secretary Wes Streeting resigned in May 2026, saying "where we need vision, we have a vacuum," and later claimed to have the backing of the 81 Labour MPs needed to formally trigger a leadership challenge under party rules.

The top two defence officials in the UK resigned on June 11, accusing Starmer of failing to invest adequately in the country's Defence Investment Plan. Business Secretary Peter Kyle publicly said Starmer was taking time to "try and reflect on the political challenges that he faces" — in British political language, roughly equivalent to a politely worded vote of no confidence.

Deadline reported that with his poll ratings rendering him one of the most unpopular prime ministers of the century, Starmer became the sixth British PM to resign from their position rather than lose at an election in the last decade.

Where It Began

The sequence of events that made Starmer's departure unavoidable began with a by-election in a small constituency in northwest England. As per reports, 2026 Makerfield by-election, the contest on June 18 was triggered by the resignation of sitting Labour MP Josh Simons, specifically to allow Greater Manchester Mayor Andy Burnham to contest the seat and become eligible under Labour rules to challenge for the leadership.

The Corportae Law Journal pointed out that it was the first time since the 1965 Leyton by-election that a contest had been triggered specifically to provide a vacancy for an individual not currently in Parliament. The Labour Party's National Executive Committee had previously blocked Burnham from standing in the February 2026 Gorton and Denton by-election before eventually clearing him for Makerfield.

Burnham won almost 55% of the 45,510 votes cast, beating Reform UK's Rob Kenyon by more than 9,000 votes, a margin that exceeded most pre-election polling projections. Nigel Farage acknowledged it was "a dramatic, emphatic win" for Burnham.

CNN's explained why the by-election's outcome was so structurally significant. Growing numbers of Labour MPs had been calling for Starmer to resign, but with Burnham ineligible to stand for the leadership while outside Parliament, no one was willing or able to formally launch a challenge. Once Burnham was in, the entire dynamic shifted.

In his victory speech, Burnham said Labour had "a final chance to change" and win back voters' trust, and spoke of building "a new politics based on unity and hope, turning away from the path that takes us to a divided, dark politics of the kind we see in the United States."

What Happens Now

Now attention has turned to whether Labour will hold a competitive leadership contest or stage a political coronation. Burnham is the frontrunner. Wes Streeting has also said he will stand if there is a contest.

The new leader will inherit a country in a difficult position. The pressure on Starmer unfolded against a broader backdrop of economic stagnation and declining public confidence, where persistent low growth, crumbling infrastructure and a perceived loss of global influence have fuelled a wider narrative of national decline. Britain's fractured relationship with Washington, its positioning on the Iran war, and the rise of Reform UK will all land on whoever takes over in September.