Voters are casting their ballots in the Holborn and St Pancras by-election to elect a new MP in Keir Starmer's old seat, with polls closing at 10pm on Thursday.
Labour's candidate Sagal Abdi-Wali, a former child refugee from Somalia, is competing against Green Party leader Zack Polanski in the London constituency. Ballots will be counted overnight.
Defining moment for Green leadership
The result could be a defining moment for Polanski's leadership of the Green Party, which has seen a surge in membership and record-breaking results in the May 2026 local elections, gaining more than 440 councillors and taking control of five councils.
Ahead of polls opening, Polanski admitted the race is "looking close". Labour sources are understood to be confident but not complacent, with insiders aware that Polanski's profile could sway the outcome.
The Greens' popularity has started to dip after Andy Burnham regained some Labour voters who had lent them their vote. Polanski has also faced a troubling week after the Green Party passed a controversial motion at its conference in Brighton asserting that "Zionism is racism".
Labour candidate's background
When Abdi-Wali was selected, she faced criticism from Reform's Zia Yusuf over not being born in Britain, an attack Labour branded "straightforward racism". In an interview with the Mirror, she hit out at the "hateful rhetoric" around her selection and issued a defiant defence of immigration.
