FORMER BRITISH PRIME minister Keir Starmer is to step down as an MP, triggering a byelection that will test his successor Andy Burnham’s Labour government. 

The announcement comes on the day that Burnham will address the House of Commons for the first time as prime minister, having taken over from Starmer in July. 

Starmer was the MP for Holborn and St Pancras, a constituency in central London that has been a safe Labour seat since its creation in 1983. 

He has informed local Labour constituency party staff of his decision to exit parliament after 11 years representing the north London seat.

It has been an honour and a privilege to represent Holborn and St Pancras for the last 11 years.

My statement. pic.twitter.com/xzu4xcIno2

— Keir Starmer (@Keir_Starmer) September 1, 2026

In an interview with his local newspaper, Starmer told the Camden New Journal that it had been “a huge honour and privilege to represent the best constituency in the country” but that it was “the right time” for him to leave office. 

“I will now focus on other things and that will be international affairs including defence, security, trade and technology in a fast-changing world,” he said. 

“I will also continue, as I have done for a long time now with others, work on combating violence against women and girls; that is an issue that matters to me hugely. It’s work I started before I became an MP and it’s work I’m keen to continue after I’m an MP.

“So international affairs on the one hand, and continuing my work on violence against women and girls on the other.”

He added that he will continue to give his full support to Burnham’s government. 

Starmer, a former human rights lawyer who served as director of public prosecutions in the UK, was first election to the House of Commons in 2015. 

After taking over the Labour leadership from Jeremy Corbyn in 2020, he led the party to a landslide election victory – with a 174-seat majority – four years later.

But the mood of optimism among Labour activists, who hoped for a calm, stable government after the turmoil of the previous decade of Tory rule, dissipated amid a succession of high-profile policy U-turns which created a sense of drift and indecision at the heart of government.

The general view on Starmer’s two-year premiership is that he failed to outline a clear vision of what he was for, while simultaneously making a series of poor decisions that reflected badly on him and Labour.

When he resigned as prime minister in July, Starmer told the BBC that he intended to remain as an MP until the next general election in the UK.

Byelection

His departure marks only the second time that the Holborn and St Pancras seat has been available in 47 years, with the Conservatives and Reform set to challenge Labour and stand candidates to replace Starmer. 

It could also be a way into parliament for Green Party leader Zack Polanski. With his party enjoying strong support in the constituency, it is thought they would mount the biggest challenge to the governing party. 

Starmer had a majority of 11,572 when he was reelected to the seat in 2024, but Labour’s vote share fell by 17 points to 48%. The Greens, whose candidate David Stansell came third behind independent Andrew Feinstein, increased their vote to 10%. 

A spokesperson for the Greens has said: “Zack has always made it clear he would like to be a London MP. London has been his home for over 20 years.”

The Tories said that Starmer’s decision to step down marked “another U-turn”.

Conservative Party chairman Kevin Hollinrake said: “Whilst we have disagreed with almost all of Sir Keir Starmer’s decisions, I wish him and his family well for the future.

“It is fitting that his final act as a Member of Parliament is yet another U-turn having pledged to stay on.

He added: “The Conservatives look forward to giving the people of Holborn and St Pancras a chance to vote for a stronger economy and a stronger country in the weeks ahead.”

With reporting from Press Association