Polls have closed in the Holborn and St Pancras byelection, a contest seen as a test of whether Andy Burnham can unite Labour's voters or whether Zack Polanski can peel off support from the party's progressive flank. This was reported by Qazaqyia.kz citing The Guardian.

Labour is seeking to retain Keir Starmer's former north London seat, where he won a majority of more than 11,000 votes in the 2024 general election.

The byelection is seen as a measure of the political landscape under Burnham, almost three months into his premiership. It is a significant first electoral test for Burnham, who succeeded Starmer in July, as part of a wider battle for younger leftwing voters who became disillusioned with the party under Starmer's leadership over issues such as housing, the climate crisis and the war in Gaza.

Polanski has sought to run an energetic campaign involving thousands of activists, leaving the Green party conference early after his speech in an attempt to prove he and the Greens are a serious rival to Labour, despite the latest polling.

The Greens are hoping to reproduce their byelection victory in Gorton and Denton in February where they overturned a Labour majority.

However, the political landscape has shifted since then. Shortly after their byelection win in Greater Manchester, YouGov polling put the Greens on 21%, a few points ahead of Labour.

But the latest YouGov survey put the Greens 16 points behind Burnham's Labour, which was on 27%. The poll came as Burnham proposed a more ambitious pitch to progressives at his first Labour conference as prime minister.

Holborn and St Pancras has a large number of students, younger voters and renters, with almost half of residents aged between 18 and 34, while about 45% were born overseas.

Polanski has argued that electing him would increase pressure on Labour to deliver more radical policies, including stronger rent controls, greater action on the climate crisis and public ownership of Thames Water.

But the leader of the Greens has faced questions about his own authority and was accused of being unable to articulate his thoughts on motions that became policies at his party's conference.

In an interview with the Guardian last Friday, Polanski described the contest as "probably 50/50" and that it was "really on a knife-edge" while also insisting his leadership did not depend on victory.

Asked whether losing the byelection would undermine his position, Polanski said: "It doesn't depend on it whatsoever."

Senior Green figures privately fear a defeat could severely damage his reputation amid concerns the party's increase in members has not translated into an advantage in campaigning.

Labour has fielded Sagal Abdi-Wali, the 42-year-old leader of Camden council who arrived in Britain as a child refugee after her family fled civil war in Somalia.

She has emphasised her longstanding connections to the area, presenting herself as locally rooted, and with experience of community work, homelessness and housing policy.

The closing days of the byelection campaign were overshadowed by a row within the Green party after members voted at their conference to adopt a policy equating Zionism with racism, which passed by 1,022 votes to 813 despite opposition from four of the party's five MPs.

Polanski, who is Jewish, left the conference early to campaign in north London and did not participate in the vote.

The byelection result may provide some insight into whether Burnham's recovery in national support is translating into Labour's inner-city strongholds, and into whether the Greens can continue to attract younger and progressive voters.

It will also offer a test of Polanski's argument that the Greens can put pressure on the government from the left, even as Labour seeks to reclaim voters it lost under Starmer.

Polls closed at 10pm on Thursday and the result is likely to be announced between 2:30am and 4am on Friday.