Green Party leader Zack Polanski is open to an election deal with Labour to stop Nigel Farage becoming prime minister – as long as Sir Keir Starmer is ousted as leader.
Senior Green officials told The i Paper that Polanski’s overriding priority at the next election is stopping Reform from winning power.
He is open to a deal with other parties, including Labour, to consolidate anti-Farage votes and prevent Reform winning seats, effectively formalising the kind of tactical voting that some predict may decide the next general election, due in 2029.
Polanski is understood to have told associates that “I couldn’t live with myself” if Farage became PM and he did not do everything possible to stop Reform.
Green officials believe there is “no advantage” to an election deal with Labour if the unpopular Starmer remains in post, not least because Polanski has spent much of his time since being elected leader in September criticising the Prime Minister and his politics.
Starmer leadership threat
However, Starmer is facing an internal threat to his leadership due to dire poll ratings, and Green officials believe he will be ousted and replaced with a candidate who is likely to move Labour to the left in order to win a leadership contest decided by the party membership.
Polanski would therefore be open to working with Labour under a new leader, with the likes of Andy Burnham or Angela Rayner much closer to his left-wing brand of politics.
A senior Green official said: “At the general election, stopping Farage is the most important objective.
“We expect to be the main challengers to Reform, but of course we are open to discussing what options exist to help in that central mission of stopping Farage.”
Party officials stressed the Greens were first working towards replacing Labour as the most popular party on the left of politics.
The Greens are now second behind Farage’s party in several constituencies, with party membership surging by 110,000 to 180,000 under Polanski, officials said.
The party is targeting victories in May’s local elections in city areas such as east and south London, Leeds, Bradford, Newcastle and Cardiff, picking up disillusioned urban Labour voters as well as energised younger voters, alongside less politically engaged people who may also be Reform-curious.
On Monday five Labour councillors on London’s Brent council announced they were defecting to Reform.
Polanski claimed their move “mirrors what we’re hearing across the country”.
Voters deserting Labour and Tories
Discussion of election deals is becoming more urgent as polling suggests voters are deserting Labour and the Tories, with just 42 per cent backing the two traditional parties in the last BMG survey for The i Paper.
The poll had Reform in the lead on 30 per cent, followed by Labour on 22, the Tories on 20, followed by the Liberal Democrats and Greens, following a Polanski-inspired surge, on 12 each, suggesting a five-way political split and a highly unpredictable 2029 election.
A separate poll in November meanwhile suggested tactical anti-Farage voting could define the next election, with 46 per cent of Green voters and 57 per cent of Liberal Democrat voters telling YouGov they would back Labour if they were best placed to stop Reform winning their local seat.

A by-election in October in Caerphilly in Wales saw nationalists Plaid Cymru take the seat from Labour, who had held it for more than a century. Observers put the victory down to a galvanising of support behind the left-leaning party in order to beat off a threat from Reform, who came second.
The Greens broke though in the 2024 General Election, winning four seats, after previously holding just one, Brighton Pavilion, with 6.7 per cent of the vote. However, they came second in 40 seats, 39 of which were to Labour.
Luke Tryl, director of More In Common, said that looking at recent polling, the Greens would be “contenders” in “at least 30 seats” in the next general election.
Even if they don’t pick up seats, they could take crucial votes off Labour, he suggested.
Around a fifth (20 per cent) of their voters backed Labour in 2024, meaning that “even if the Greens don’t win many seats themselves, it could cost [Starmer’s party] many seats to Reform, or the Tories if there is a revival”.
“So on paper a pact sounds good,” Tryl told The i Paper.
‘Two big problems’ for Polanski
But he said there were “two big problems”, including that “most of the Green target seats are current Labour-held seats and traditionally safe ones at that – how do you have a pact with a party that is targeting your seats?”
Tryl also warned that “being seen to be in de facto coalition with Greens might help with progressives but would leave Labour open to charge of endorsing his more left leaning propositions on migration or Nato which would hurt them with their right flank”.
Chris Hopkins, political research director at Savanta, told The i Paper: “A divided ‘left’ would always benefit Reform, and it could be the difference between a Reform election victory or not.
“Their greatest electoral asset, other than the cult of personality behind Nigel Farage, is the rest of the electorate fragmenting, lowering the threshold in each constituency any party would need to win.
“Reform’s support at the moment is relatively evenly spread, meaning they’ll win seats if the electorate remains fragmented, but may not where other parties can ‘concentrate’ their support better.
“Labour and the Greens doing a deal naturally concentrates that support and therefore could be effective.”
A Government source dismissed the idea of a Labour pact with the Greens, saying “we are not even thinking about that”.
“We need to focus on being a viable government.”
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They also suggested Polanski and the Green Party’s surge would be halted as voters get to know him better, including a controversial stint as a hypnotherapist when he claimed he could increase the size of women’s breasts with the power of his mind, for which he has apologised.
“The hypnotist thing goes down in focus groups like a bucket of cold sick,” the Government source said.
Asked whether the party would rule out a deal with the Greens, a Labour source said: “The British people voted for Labour to deliver a decade of national renewal at the last election. Zack Polanski doesn’t have a plan to take this country forwards – he can dream about doing fantasy deals all he likes, we’re getting on with improving the lives of working people.”