Green Party leader Zack Polanski has said he intends to stand as a candidate in the Holborn and St Pancras by-election, triggered by Sir Keir Starmer’s exit from Parliament.

Mr Polanski announced his hope to contest the seat and win a place in Parliament to the Camden New Journal.

His intervention in the contest could provide an early test of Andy Burnham’s popularity with the public, as voters in the seat have moved away from Labour towards Green and independent candidates in recent years.

“I have lived and worked in this community over many years, I know it well and I love it,” Mr Polanski said in an interview with the north London newspaper.

“It represents so many of the things that make London so special. I am so excited by the prospect of representing this place in Parliament.”

Mr Polanski is yet to have been formally selected by local party members as their candidate for the constituency, but his comments suggest he is confident this will happen.

Reports in recent days have suggested there are splits among Green Party activists about whether they should instead choose an explicitly pro-Gaza candidate for the race.

Former prime minister Sir Keir announced he would quit as an MP on Tuesday, as Parliament returned from its summer recess, despite having previously insisted he would stay on as a backbencher until the next general election.

He was soon after appointed to the position of “steward and bailiff of the Three Hundreds of Chiltern”, as part of an archaic formal process which allows an MP to resign.

Mr Polanski, who is currently a member of the London Assembly, told the Camden New Journal that the constituency had “been held back by governments who have failed to make the changes to improve people’s lives”.

He added: “We know that the Greens can win here, and by electing me, voters will have someone who will always fight their corner – never scared of big donors or the party whip.

“Too often Labour has stood up for corporations and big money. I will stand up for people struggling to pay their bills.”

The Greens are likely to pose the greatest threat in the by-election to Labour, which has held the inner London constituency continuously since the seat was created in 1983, winning at least 40% of the vote at every election.

Only two Labour MPs have ever represented Holborn and St Pancras: former health secretary Frank Dobson, from 1983 to 2015, then Sir Keir.

At the most recent general election in 2024, Sir Keir held the seat with 48.9% of the vote, ahead of independent candidate Andrew Feinstein in second place on 18.9% and the Greens in third on 10.4%.

The Conservatives came fourth on 7.2%, Reform finished fifth on 6.1% and the Liberal Democrats were sixth on 5.8%.

The popularity of the independent and Green candidates at the 2024 contest, finishing second and third respectively, may have been partly down to former Labour voters protesting against Sir Keir’s refusal to take a stronger position on Israel’s actions in Gaza in the war with Hamas.

The Green Party also made gains in the May local elections in the London Borough of Camden, the local authority which covers the constituency.

A date for the Holborn and St Pancras by-election has not yet been set.

Asked if the Tories had a chance of securing the seat, Conservative Party leader Kemi Badenoch said: “If people want to vote for someone who can hypnotise them, they can vote for Zack Polanski.

“If they want to vote for someone who is going to spend all their money on debt projects, they can vote for Burnham’s candidate.

“But if they want someone who is fiscally responsible … who is going to improve their living standards and get growth, then they can vote for the Conservative candidate, and we will be standing someone there.”