The Tories lost more than 1,200 seats, while the Lib Dems gained more than 600. The Greens gained more than 180 seats, with party co-leader Jonathan Bartley declaring it “the biggest election night in our history”.
Change UK MP Chuka Umunna said the local election results illustrate that “politics is broken in Britain”, while polling expert Sir John Curtice said the hold of the two big parties looks “as weak as it has done at any point in post-war British politics”.
The prime minister was confronted with anger as backbench MPs called for her removal and warned that the party would be “toast” if it did not change direction.
In Wales, a heckler interrupted the PM as she gave a speech in Wales, saying: “Why don’t you resign? We don’t want you.”
The prime minister later thanked Conservative councillors who had lost their seats.
“Because we haven’t delivered the Brexit deal through parliament yet, this was going to be a particularly challenging set of elections for both of the main parties,” she said in a speech to the North East Lincolnshire Conservative Group.
“I also know that last night, I’m sorry to say, a good number of good local councillors across the country lost their seats,” she said, in a speech to the North East Lincolnshire Conservative Group.
“Brandon (Lewis) and I both started our careers in local government and we know what it’s like when you’re fighting local elections against a difficult national background.
“I’d like to thank all those councillors for all their hard work and effort that they’ve put in.”
Labour also suffered losses, surprising the party leadership who had expected to make gains in Thursday’s vote.
Instead the party lost 63 council seats and overall control of six councils, including heartland councils such as Hartlepool, Wirral and Bolsover.
Both parties are now bracing for further losses in European elections, which are scheduled for 23 May.
If you would like to see how the results emerged, please see what was our live coverage below:
Good morning, and welcome to The Independent's live coverage of Brexit and the local council elections.
The Conservative party is forecast to lose hundreds of seats in local council elections, as the electorate punishes Theresa May's party over its failure to deliver Brexit.
The results will give an indication of how the prime minister's failure to depart from the EU on 29 March has affected support for her party.
According to one analysis, Tory losses could top 1,000.
Labour are expected to make gains in the local elections, as are the Liberal Democrats.
Theresa May sacked Gavin Williamson, her defence secretary, last night, after he was named as the source of the Huawei leak. Rob Merrick has the full story:
Labour's deputy leader Tom Watson has been granted an emergency question to ask Theresa May if she will make a statement on the findings of the inquiry into the Huawei leak, according to Labour.
The chairman of the parliamentary Intelligence and Security Committee, Dominic Grieve, told Sky News: "If people leak the content of such a meeting - even if it is just about a policy disagreement, not some specific secret item - it ruthlessly undermines the ability of the National Security Council to do its work.
"And it is totally unfair on colleagues, and indeed unfair on anybody who attends.
"I have noted that Gavin Williamson denies this, but the fact that there has been a leak has precipitated this crisis, so from wherever it came or may have come, it shows just how corrosive and undesirable it is."
Asked if Mr Williamson should face a criminal investigation, Mr Grieve said: "If you are going to leak material from a National Security Council meeting which includes classified material, potentially you do break the law.
"But in this country, investigation of criminal offences is done independently by the police and Crown Prosecution Service. It's not a matter directly for the Government, although it could be referred to the police."
A government minister is to be summoned to the House of Commons to answer MPs' questions on the leak inquiry which led to Gavin Williamson's dismissal.
Speaker John Bercow granted Labour deputy leader Tom Watson an urgent question on the findings of the inquiry, which was directed at Theresa May, but it is unclear whether the prime minister will respond in person or send another minister.
Here's a YouGov poll for The Times' Red Box suggesting 30 per cent of voters intend to vote for the Brexit Party in the European parliament elections. Nigel Farage's new party was followed by Labour and then the Conservatives.
The by-election to find a replacement for Fiona Onasanya in Peterborough will be held on 6 June, after Labour moved a writ in Parliament the morning after she was removed as Independent MP for the city by a recall petition.
My colleague Ashley Cowburn has the story on the by-election here:
Labour deputy leader Tom Watson has called for a criminal investigation into whether former defence secretary Gavin Williamson leaked official secrets over Huawei.
He told the Today programme: "This is about the law applying equally and to everyone.
"We have had high-profile civil servants go to jail for breaching the Official Secrets Act.
"The logic of the Prime Minister's letter is she says she has compelling evidence that suggests he has done the same.
"He is denying it and he has the right to clear his name - the way to do that is a criminal inquiry if confidential information has leaked."
Labour has called for Gavin Williamson to be prosecuted under the Official Secrets Act after he was sacked by the prime minister. Here's my colleague Rob Merrick with more information:
Foreign Secretary Jeremy Hunt said the police, not politicians, should decide whether to launch a criminal investigation into the Huawei leak.
In response to a question from the Press Association during a World Press Freedom Day forum at the African Union in Addis Ababa, Ethiopia, Mr Hunt said: "Let me say that, when it comes to issues like whether there should be a police investigation or not, there's a very, very important principle of our system that those decisions are not made by politicians, they are made independently by police.
"And that has to be the correct way forward in this situation."
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