Green Party leader Zack Polanski has confirmed that he wants to fight the Holborn and St Pancras by-election triggered by Sir Keir Starmer’s departure from Parliament, setting up the prospect of a high-profile battle with Labour in the former prime minister’s old constituency.
Polanski has publicly declared his intention to seek the seat and said he was “so excited” by the prospect of representing Holborn and St Pancras in the House of Commons.
There is, however, an important procedural qualification: Polanski has not yet completed the local Green Party selection process. His candidature must still be approved by party members in the constituency before he formally becomes the Green candidate.
The Green leader’s decision nevertheless transforms a contest that was already likely to attract national attention into an early electoral test for Prime Minister Andy Burnham and Labour.
Polanski says Greens can win
Polanski said he had lived and worked in the community over many years and argued that the constituency represented many of the things that made London special.
He said the Greens believed they could win the seat and promised to make affordability a central issue in his campaign, contrasting his party’s approach with Labour and accusing it of standing up for corporations and big money.
Those criticisms are Polanski’s political claims and form part of the Green Party’s attempt to frame the by-election as a direct contest with Labour rather than an assessment of Starmer’s personal record in the constituency.
The Green Party had already described the contest as a potential “referendum on ending Rip-off Britain” before Polanski publicly confirmed his intention to stand.
Starmer won by 11,572 votes in 2024
Holborn and St Pancras has been represented by Labour for decades and Starmer retained the constituency comfortably at the 2024 general election, but the detailed result gives the Greens grounds for believing that the coming contest could be significantly more competitive.
Official Camden Council results show that Starmer received 18,884 votes in 2024.
Independent candidate Andrew Feinstein finished second with 7,312 votes, while Green candidate David Stansell received 4,030. Reform UK received 2,371 votes, the Conservatives 2,776 and the Liberal Democrats 2,236.
Starmer’s majority over Feinstein was therefore 11,572 votes.
Although simply combining the 2024 Green and independent votes would still have left Starmer ahead, by-elections can produce substantially different voting patterns from general elections and Polanski’s position as a national party leader gives the Greens a much higher-profile candidate than they fielded in the constituency two years ago.
Greens made major gains in Camden
The Greens can also point to more recent evidence of local electoral strength.
At the May 2026 Camden Council elections, the party made significant gains and became a much stronger force in the borough.
In Holborn and Covent Garden ward, which lies within the parliamentary constituency, Green candidates Hamza Chowdhury, Jim Monahan and James White won all three council seats. Official Camden results recorded 1,271 votes for Chowdhury, 1,176 for Monahan and 1,144 for White.
That result does not automatically translate into support across the entire parliamentary constituency, but it demonstrates that the Greens have an established electoral base in at least part of the seat they are now targeting.
First major by-election test for Burnham
The timing gives the contest wider political significance.
Starmer announced on 1 September that he would leave the Commons after 11 years as MP for Holborn and St Pancras. He said he wanted to concentrate on international affairs, including defence, security, trade and technology, alongside continuing his work on violence against women and girls.
His departure came only weeks after he left Downing Street and was succeeded as prime minister and Labour leader by Andy Burnham.
That means the resulting by-election will be one of the first significant tests of voter sentiment since Burnham took over the Government.
Labour will enter the contest defending a seat it has held continuously since the constituency was created in its present form, but it will now face the leader of a rival party attempting to turn the campaign into a national political event.
Polanski still needs local approval
Despite the announcement, Polanski should not yet be described as the formally selected Green candidate.
Local party members must approve the candidature through the Green selection process. Reports indicate that the process is expected to conclude shortly and that Polanski is not expected to encounter significant opposition, but until that vote takes place his status remains that of a prospective candidate seeking selection.
If selected, Polanski would enter the race as one of the most prominent Green parliamentary candidates in the party’s history and with the opportunity to secure his own place in Westminster.
He currently serves in the London Assembly but does not sit in the House of Commons.
Battle for Starmer’s successor begins
Labour is also moving rapidly to choose its candidate, with the party operating an accelerated selection timetable following Starmer’s announcement.
The eventual contest will therefore be about more than simply replacing a former constituency MP.
For Labour, retaining Holborn and St Pancras would provide Burnham with an early electoral victory in a historically safe seat. For the Greens, a competitive result — let alone victory — would provide evidence that the party can translate its recent local gains and increased national profile into parliamentary representation in London.
Polanski’s announcement means that battle has now effectively begun, even though the final Green selection formalities still have to be completed.
Sources
- Green Party: Holborn and St Pancras by-election statement — 2 September 2026
- Camden Council: 2024 parliamentary election results
- Camden Council: Holborn and Covent Garden ward 2026 results
- Reuters: Polanski confirms intention to contest Holborn and St Pancras — 3 September 2026
- Camden New Journal: Sir Keir Starmer to step down as MP — 1 September 2026