Questions arose about Zack Polanski's account of his own position after he stated he had stood against his party's "Zionism is Racism" motion, a claim that sat uneasily with his decision to abstain from the vote when the matter came before conference.

Following the Green Party's by-election defeat to Labour in Holborn and St Pancras, Caroline Lucas — the party's founding MP and a former leader — raised concerns about the current leader's public silence on the motion. Polanski attributed his absence to the demands of running his by-election campaign.

Speaking to a broadcaster, he described a by-election then under way — one he characterised as among the most consequential votes in the country's recent memory — and noted that supporters in that contest had called for his presence on the ground. He noted that local matters were what his constituents wanted addressed, and he acted accordingly, adding that the motion in its amended form would have had his backing. He went on to express agreement with the motion's substance, noting that it had not been amended.

Vivien Lichtenstein, chair of Jewish Greens, called on Polanski to step down from his position after his loss in the by-election, while separately expressing disagreement with the notion that the Green Party ought to be determining the region's future direction. Her objection extended to his handling of the "Zionism is racism" motion, where his failure to speak out drew her assessment that staying silent had been a considerable error in judgement.

In an interview with a broadcast outlet, Lichtenstein pushed back against claims by senior Green Party figures that Jewish members had been consulted before the motion was put forward. Lichtenstein noted that the Jewish party members involved remained unknown to them, adding that no engagement had taken place with the Jewish Greens committee. Susan Hall, who leads the Conservatives on the London Assembly, posted on social media that the timing of the statement — coming only after the vote — drew her attention.

Some parties on the left have drawn criticism for appearing to place the conflict in Gaza ahead of domestic concerns. Unverified claims have circulated attributing the move to electoral calculation rather than policy conviction. The by-election result drew a notably poor assessment for the Green Party.

In a joint statement released last week, the Jewish Leadership Council and the Board of Deputies characterised the Green Party as an organisation whose passage of the motion equating Zionism with racism had, in their view, exposed a disposition toward extremism. A statement issued on their behalf directed particular disapproval at Zack Polanski, noting that he had neither spoken against the motion nor cast a vote on it.

Labour retained the Holborn and St Pancras constituency, previously held by Sir Keir Starmer — who served as prime minister before stepping down from his parliamentary seat. Lichtenstein described his conduct as that of an onlooker rather than someone exercising leadership. A total of 12,292 votes were cast in favour of Sagal Abdi-Wali, securing her a place in parliament, while a tally of 8,928 ballots was recorded in Polanski's favour. Galloway's Workers' Party standing in the contest yielded a tally of just 314 votes, a figure too low to secure the return of his deposit.

Polanski announced an intention to remain at the helm of the Green Party, notwithstanding the absence of a parliamentary seat following the election. Doubts about the Green Party of England and Wales leadership had already been voiced by prominent figures within the party before the by-election in Holborn and St Pancras — triggered by the departure of former prime minister Sir Keir Starmer from his parliamentary seat — delivered a result that went against the party's leader. Polanski expressed confidence in his ability to continue leading the party, while noting that Green members would hold the final say over his position.