Zack Polanski, the leader of the Greens in England and Wales, has discovered that running for Keir Starmer’s old seat comes with unexpected opposition - from his own party. Hamza Chowdhury, a Green councillor on Camden council, has thrown his hat in the ring for the Holborn and St Pancras byelection, scheduled for 8 October, and he’s not mincing words about his national rival.

Chowdhury, who has secured nominations from six other Camden Green councillors (seven of the ten Greens on the authority, if you’re counting), took to Instagram on Monday to argue that the seat doesn’t need “a politician you’ll only see on a leaflet.” He painted a picture of local woes - broken lifts, unpicked bins, unclean roads, and an endless housing register - and insisted he knows them because he lives them daily, unlike Polanski, who resides in east London’s Hackney.

The timing adds a dash of irony: the byelection falls just a week after the Green party conference, meaning the final campaign weekend will see activists decamped to Brighton. Polanski, who announced his candidacy on Thursday, acknowledged his underdog status in a constituency Starmer won with an 11,000-plus majority in 2024. He’s already deployed canvassers, hoping to replicate the Greens’ February upset in Greater Manchester’s Gorton and Denton, where they overturned a 13,000-plus Labour majority.

But Chowdhury’s challenge is notable, especially with the backing of Lorna Russell, the Greens’ group leader in Camden. Polanski, undeterred, told the Guardian he won’t move to the area even if he wins, but will cycle from Hackney - because, as he put it, “the length of the constituency is just as fast for me to cycle.” Local party members vote later this week, and while they’re reportedly broadly supportive of Polanski, the spectacle of a Green leader fighting his own councillors for a seat might just be the freshest thing on the ballot.