Labour has jumped to a five-point lead over the Conservatives, according to a poll published on Friday.
The Ipsos MORI survey put Labour on 42% with the Conservatives on 37%. The Lib Dems trail in third with 8% while the Green Party was fourth on 5%.
It is the first time Labour has been ahead of the Tories in poll conducted by the firm since Boris Johnson became prime minister in July 2019.
Johnson also scored the worst rating as PM he has received, with 33% satisfied, 59% dissatisfied, a net satisfaction rating of -26%.
Keir Starmer meanwhile has held onto a net positive satisfaction rating of +15, with 45% satisfied and 30% dissatisfied.
According to Ipsos MORI, of opposition leaders going back to Michael Foot, who led Labour between 1980 and 1983, only Tony Blair had better net satisfaction ratings at this stage of his leadership (+26).
The poll, for the Evening Standard, was conducted between October 22 and October 28 as Boris Johnson faced a huge backlash over his refusal to fund more free school meals for hungry children.
It also comes as the death toll from the coronavirus second wave started to mount, with experts warning the UK is now at a “critical stage” with infections doubling every nine days.
This week, the daily death figures topped 350, meaning the UK has shot past an earlier warning by chief scientific adviser Patrick Vallance that the country could see 200 coronavirus deaths a day by mid-November.
Almost a fifth of England’s population will soon be living under the country’s toughest Covid-19 rules.
Starmer’s political director, Jenny Chapman, said the poll was “encouraging” for Labour.
But the results were gathered before the Labour was plunged into a new civil war following the publication of an Equality and Human Rights Commission report into anti-Semitism in the party.
It found Labour has been responsible for unlawful acts of harassment and discrimination.
Jeremy Corbyn was dramatically suspended from Labour on Thursday, after he rejected some of the equality watchdog’s findings and claimed the issue had been “dramatically overstated for political reasons” by his critics.
This put him at odds with Starmer, who had warned that any suggestion allegations of anti-Semitism in Labour while Corbyn had been leader were exaggerated would not be tolerated.
And speaking to BBC Radio 4′s Today programme on Friday, Starmer said it was possible Corbyn’s suspension from the party could be escalated to an expulsion.
“I’m deeply disappointed in that response from Jeremy Corbyn yesterday” the Labour leader said. “I don’t want a civil war in the Labour Party, I don’t think there is any need for one.”
Allies of Corbyn have rallied to his defence. Unite union boss Len McCluskey called the suspension an “act of grave injustice” which could “create chaos within the party” and put any chance of election success in jeopardy.
Ex-shadow chancellor John McDonnell described the suspension as “profoundly wrong”.
Ipsos MORI conducted 1,007 interviews by telephone October 22 and October 28.