The Conservatives risk being “almost annihilated” at the general election, one of the country’s leading polling experts has warned.
Professor Michael Thrasher said the results of the local elections looked to be “very bad news” for Rishi Sunak.
The Sky News election analyst said the Conservative vote had collapsed among its base of Leave voters.
Early results showed the Tories are well on course to lose hundreds of council seats across England.
“If the Conservative fall as low as these council elections so far appear to be telling us, then we’re in a situation that we were in [back] in 1997, where the Conservative vote fell so far down that they were almost annihilated,” Thrasher said on Friday morning.
“The same fate awaits the Conservatives at the next general election if their vote slides this far below, say, 30% in a general election.”
Keir Starmer said Labour had taken a “giant step” towards forming the next government, as the party seized control of key Tory councils across England.
“We want a general election, we want to win that general election, we want to take our country forward,” he said on Friday morning.
Labour gained Hartlepool, Rushmoor and Redditch directly from the Conservatives in a boost for Starmer.
The party took control of Thurrock Council in Essex, which was Tory-run as recently as last year, and deprived the Conservatives of their majority on North East Lincolnshire Council.
Labour also won the Blackpool South by-election as the Tory vote collapsed by 32%.
Professor John Curtice, the BBC’s elections guru, said the by-election victory was “spectacular”.
“It was the third biggest swing from Conservative to Labour in post-war in postwar by-election history. And it’s the third biggest drop in the Conservative vote in postwar by-election history,” he said.
“This is now the fifth by election in which the swing has been over 20%. There have haven’t been much more than a dozen of those in the whole of the post war period.
“When was the last time that such swings occurred as more than a rare event? Well, it was the parliament of 1992 to 1997 which ended with Tony Blair winning a landslide victory.′
However, there were signs that Labour’s stance on the war in Gaza was hitting the party’s support in Muslim communities. That led to the party losing control of Oldham Council in Lancashire, and the Greens making major gains in Newcastle and South Tyneside.
Richard Holden, the Conservative party chairman, admitted it was “not a great set of results”, but sought to play down their significance.
And he dismissed suggestions Sunak could be ousted by Tory MPs panicked about a looming general election defeat.
“The prime minister is going to go on and lead the Conservative party into the general election, there’s no doubt about that,” he told the BBC.