Zack Polanski has been selected to lead the Green Party’s bid to prise Sir Keir Starmer’s former Commons seat away from Labour.
The Greens confirmed this morning that their high-profile, populist party leader will stand in the Holborn and St Pancras by-election on October 8.
Polanski secured the nomination ahead of local councillor Hamza Chowdhury, who had criticised the practice of “famous” candidates being dropped into constituencies for elections before later moving on.
If elected, Mr Polanski has said he would commute to Holborn from his home in fashionable east London. He will face Labour candidate Sagal Abdi-Wali in the contest, which was prompted by former prime minister Sir Keir’s exit from Parliament.
Holborn and St Pancras has been a Labour seat since its creation in 1983, but Green Party figures believe the by-election gives them a genuine opportunity to stage a major political upset.
Taking to the stage after a speech from Green MP Hannah Spencer, Mr Polanski said he was already fighting back tears before declaring: “We have the momentum and we can win.”
He also expressed support for Ms Abdi-Wali, a former child refugee born in Somalia, following what he described as “despicable” comments about her background by Reform’s Zia Yusuf on X.

The Green Party leader was announced this morning as the party’s candidate for the October 8 Holborn and St Pancras by-election.

Mr Polanski is set to go up against Labour’s Sagal Abdi-Wali, the leader of Camden Council, after former prime minister Sir Keir left Parliament.
“Every single day during this election, I will stand with any candidate who is facing abusive attacks and at the same time put forward Green Party policies that are going to make life easier for everyone in this country and in this constituency,” he told reporters.
Ms Spencer said Green members in the area had “overwhelmingly” backed Mr Polanski, a London Assembly member, over Mr Chowdhury to become the party’s candidate.
The Holborn and St Pancras by-election is also expected to serve as an early measure of Prime Minister Andy Burnham’s standing with voters.
The Greens are likely to pose the greatest threat to Labour in the contest, but there is also much at stake for Mr Polanski’s party.
Support for the Greens surged in his first year as leader but the party’s national polling has dipped since Mr Burnham replaced Sir Keir in Downing Street.
Mr Polanski, a London Assembly member, has previously said he was ‘excited’ by the prospect of winning the seat and entering the Commons.
He dismissed suggestions from rival Mr Chowdhury that the constituency did not need ‘another MP who arrives during an election campaign’ then ‘disappears once the votes are counted’.
‘I think the local party already knows that doesn’t describe me at all. It’s a place that I know very, very well,’ Mr Polanski said on Wednesday.
‘I’m excited for this campaign because I think the Green Party and I have a real story to tell and I’m confident, but not complacent, I’ll be out there campaigning for every vote, that it’s a message that will resonate with people in Holborn and St Pancras.’
Ms Abdi-Wali, who has led Camden Council since May this year and been a councillor for Camden Square since 2022, will seek to retain the seat for Labour.
Mr Burnham visited the constituency on Thursday to support Ms Abdi-Wali on her first day of campaigning, she said in an X post.
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 per cent of the vote, ahead of independent candidate Andrew Feinstein in second place on 18.9 per cent and the Greens in third on 10.4 per cent.
The Conservatives came fourth on 7.2 per cent, Reform finished fifth on 6.1 per cent and the Liberal Democrats were sixth on 5.8 per cent.
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 that covers the constituency.
Government chief whip Anneliese Midgley moved the writ in the House of Commons on Monday, officially triggering the by-election.
Sir Keir revealed his plans to leave Parliament earlier this month, saying he felt it was the ‘right time’ to step down and focus on new work on international affairs.