ZACK POLANSKI’S decision to contest the by-election in Holborn and St Pancras dramatically raises the stakes in that poll.

The involvement of the Green Party leader — subject to selection by local party members — turns the race to succeed the unmissed and unmourned Keir Starmer into a struggle over the direction of progressive politics in Britain.

Some of the tactical considerations which have informed other recent Commons by-elections do not apply in the north London seat.

There is no chance of Reform making more than a marginal impact. The far-right party gained very limited traction across London in the May elections.

Holborn & St Pancras has been a Labour stronghold for generations. For many years it was represented by Labour politicians genuinely rooted in their communities, from Jock Stallard and Lena Jeger to Frank Dobson.

It was Starmer’s signal achievement to cut Labour’s vote from 36,000 in the dismal election of 2019 to just 18,000 in 2024. This still left Labour with a majority of more than 11,000, but it was a drop of more than 20 per cent, a personal rejection entirely overlooked by mainstream media at the time.

The main challenge to Starmer in 2024 came from the powerful pro-Palestine campaign run by former South African MP Andrew Feinstein. His vote and the Greens combined came to nearly 30 per cent of the poll.

Nevertheless, amid a national collapse, Labour still retained control of Camden council in May, performing rather better than in many other parts of London. The Greens are not as strong in Camden as in other London boroughs, like Hackney.

So Polanski is making a bold move, seeking to reverse the drop in the Greens’ poll ratings since Andy Burnham displaced Starmer.

The new Prime Minister is clearly aiming to rebuild Labour as the natural home for progressive voters, the traditional coalition Starmer comprehensively shattered. Indeed, there is no future for the Labour Party on any other basis.

Holborn & St Pancras will pass an early opinion on his success. The Morning Star has refrained from rushing to judgement, but the signs so far do not indicate the comprehensive break with Starmer’s neoliberalism, imperialism and authoritarianism which is required, and indeed which Burnham promised.

A key issue will be the extent to which new Foreign Secretary Ed Miliband delivers on his promise, emphatically stated in the Commons this week, to bring forward a major package of sanctions against Israel.

Nothing eroded Labour’s support in Camden more than Starmer’s backing for Israel’s genocide. An unambiguous break with the policy of support for Benjamin Netanyahu’s atrocities and aggression is an essential prerequisite for winning back left-wing voters.

The Greens have been admirably clear on that issue, leading to the usual smears against the party and Polanski personally.

Other issues will be at stake too, of course. Polanski today accused Labour of pandering to big business and big money. It is up to Burnham to prove him wrong.

At very least, the Green leader will hold the new Labour administration’s feet to the fire. If Labour chooses a candidate from the Starmer gang which has dominated the local party for years, it will make its task all the harder.

It is too early to determine how the left should cast its vote. No date for the poll has yet been set.

However, the political imperatives are clear — forcing a fundamental change in the domestic and international direction of the Labour government before power is handed over to a far-right Farage-led government bent on reinforcing every bitter aspect of the “40-year wrong turn” Burnham has rejected in rhetoric but not yet in practice.