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Sir Keir Starmer has vowed to “keep on fighting” after a devastating by-election loss to the Greens heaped further pressure on the embattled prime minister.
Labour slumped to third place in its longstanding stronghold of Gorton and Denton in Greater Manchester, with Reform UK finishing second.
It marks the first win for the Greens in a by-election, with 34-year-old plumber Hannah Spencer becoming the party’s first ever MP in the north of England.
The result has led to renewed criticism of Sir Keir’s leadership from Labour MPs ahead of May elections in Scotland, Wales and some English councils that are now widely seen as a crucial test of his premiership.
Sir Keir had entered the Gorton campaign in a vulnerable position, amid dreadful poll ratings and a damaging series of policy U-turns in recent months that have prompted some Labour MPs to openly question his leadership.
Speaking after the result, he pledged to “keep on fighting”, insisting he was “getting on with the hard yards” of turning Labour’s fortunes around.
But his former deputy Angela Rayner – seen as a possible challenger to Sir Keir from the left of the party – said Labour’s defeat must come as a “wake up call” and called on the government to be “braver”.
Others blamed the prime minister’s decision to block Greater Manchester mayor Andy Burnham, another potential leadership candidate, from standing in the seat, which Labour had previously held for nearly a century.
Burnham is yet to comment on the result, and declined to speak to reporters outside an event in Manchester he attended on Friday evening.
The by-election had been billed as a key strategic test for Labour, in a largely working-class suburb of Manchester that also contains a large number of students and a big Muslim population.
In a letter to his MPs after the defeat, Sir Keir accused the Greens of embracing a “divisive, sectarian” form of politics, adding they had demonstrated they were “not the harmless environmentalists they pretend to be”.
Branding the Greens’ policies “extreme,” he insisted the party lacked the “resources, the activist base or the local knowledge to replicate this victory” during a general election campaign.
His reaction was met with an angry response from Green leader Zack Polanski, who accused the prime minister of trying to “smear voters as extremists”.
Spencer, who becomes the fifth Green MP in the Commons, also dismissed accusations of sectarian politics during the campaign, insisting her party had united voters with commons concerns about the cost-of-living, public services and the war in Gaza.
The new MP, who sits on the local council, said: “I know in my heart, and everyone knows here, everybody here belongs.
“Everybody deserves to have their needs met. Everyone deserves a voice in our democracy.”
She said the result – in what the party has said was its 127th target seat – showed the Greens “can win anywhere” and was “just the beginning” for her party, predicting further gains in elections to English councils and the Welsh Senedd in May.
Since taking charge of the Greens five months ago, self-described “eco-populist” Polanski has courted voters with a left-wing pitch on the economy, alongside its traditional focus on environmental issues.
Its policies include giving councils the power to control rents, extending free school meals to all children, and a imposing a new ‘wealth tax’ on assets above £10m.
The by-election also saw Democracy Volunteers, a group of election observers, report an “extremely high” number of instances where voters were seen trying to influence others in polling booths, a criminal offence known as ‘family voting’.
The group said it observed 32 cases of family voting among 545 voters it monitored casting their ballots at 15 stations across the constituency.
The reports were seized upon the Conservatives and Reform, with both parties calling on the Electoral Commission to launch an inquiry into the claims. The elections watchdog has said it will “carefully consider the points raised”. Reform has also called on police to investigate.
Reform UK candidate Matt Goodwin said his party had “embarrassed Labour in one of their strongest seats”.
He described the Green victory as a “coalition of Islamists and woke progressives”, marking “the emergence of a dangerous sectarianism in British politics”.
Conservative leader Kemi Badenoch said the result “shows Keir Starmer’s premiership is finished” and the PM would resign “if he had any integrity”.
Although her party was not expected to challenge in the contest, it had a dreadful night at the polls, registering just 706 votes and losing its election deposit, along with the Liberal Democrats.
So far public condemnation of Sir Keir following the result has largely been confined to frequent critics of his leadership, including Labour backbenchers such as Karl Turner, Richard Burgon, and Nadia Whittome.
However, more MPs told BBC Radio 5 Live’s Matt Chorley on the condition of anonymity that the PM should stand down.
One described the by-election result as “a punch in the face for the Labour Party and for Keir Starmer’s premiership”.
“Keir must reflect on how unpopular he is with the public,” another said.
However, others advised caution, with one Labour MP saying the party needed to “avoid knee-jerk responses that address the concerns of one wing of the support we need, at the expense of losing the other”.
Another said there was “no obvious alternative” to Sir Keir and a holding a leadership contest would be “disastrous”.
