Zack Polanski is facing a fight to get selected as the Green candidate in the Holborn and St Pancras by-election after one of his own party members mounted a challenge against him.

Camden councillor Hamza Chowdhury launched his campaign to replace Sir Keir Starmer this week by stating the borough does not need “a politician you’ll only see on a leaflet”.

Mr Chowdhury said he had received nominations from six Camden Green councillors to challenge their party leader to run in the high-profile by-election, set to be held on October 8.

The Greens won 11 seats on the local authority at the local elections in May.

Party insiders stressed that some of Mr Chowdhury’s supporters would actually back Mr Polanski to be the candidate but wanted to widen the ballot.

Nominations closed on Monday night with a decision set to be made on Thursday and announced on Friday.

Labour has shortlisted three Camden councillors, including borough leader Sagal Abdi-Wali, with the winner set to be announced on September 9.

In a post announcing his candidacy on Instagram, Mr Chowdhury said: “As a British Bengali who was born here, I believe a Global Majority candidate is best placed not only to win this seat, but to properly represent the extraordinary diversity of the communities who call Holborn & St Pancras home.

“I am from Holborn, I live here, and in May I was elected in a landslide victory in Holborn & Covent Garden by 70% from the opposition.

“I know Camden because I live it every day. I know the challenges facing our communities, our estates, our broken lifts, our unpicked bins, our unclean roads and endless housing register waiting list because these are the places I have grown up and continue to call home.

“We don’t need another MP who arrives during an election campaign, puts out a few leaflets, makes a few promises and disappears once the votes are counted. We need an MP who is present, accessible and visibly part of the community all year round.”

Mr Polanski launched his move to enter Parliament last week after Sir Keir quit as the MP for the North London constituency.

“I have lived and worked in this community over many years, I know it well and I love it,” he told the Camden New Journal.

He has already been seen campaigning in the seat.

The London Assembly has said he will not be moving to the constituency even if he wins the by-election and will instead commute from his home in Hackney.

The Greens intend to flood the seat with activists, as they did in the Gorton and Denton by-election.

But the October 8 date of the poll could potentially be problematic for the Green Party as it comes just a week after the party’s annual political conference, where politicians and many party activists will be gathered in Brighton.