• Video report by ITV News Correspondent Joe Pike

Theresa May must set a date for her departure or her MPs will do it for her, a former Conservative Party leader has said in the wake of“devastating” local election results.

Iain Duncan Smith described the polls as a “judgment on leadership” as he urged the “caretaker” Prime Minister to say when she will stand down.

The Conservatives had dropped nearly 1,300 seats and lost control of 45 councils after the final results came in – the worst performance, in raw numbers, by a governing party in local elections since 1995.

Mr Duncan Smith said the 1922 Committee of backbench Tory MPs should urgently meet again to decide on Mrs May’s fate.

“We have to make a change… The message was loud and clear that, since March 29, people have decided they are absolutely furious with the political class,” he told LBC.

“The committee has to sit again now, urgently, and decide that either the Prime Minister sets the immediate date for departure or, I’m afraid, they must do it for her.”

The threat of an imminent challenge to Mrs May’s position as Conservative leader was lifted last month when the 1922 Committee’s executive rejected calls to change party rules which protect her from a no-confidence vote until December.

Justice Secretary David Gauke said the results were Credit: Dominic Lipinski/PA

Mr Gauke said the results were “very disappointing”, telling BBC Breakfast: “What we need to be doing is addressing the big issue in front of us, which is Brexit.

“We would have had a much better set of election results had we managed to get the Prime Minister’s meaningful vote through earlier this year and we left the European Union on March 29.

“I think we can look at those local election results as a punishment for both the Labour Party and the Conservative Party for failing to find a way through that situation.”

Health Secretary Matt Hancock said that the message from voters in local elections was: “Get on, deliver Brexit and then move on.”

He said: “The electorate… right across the country want us to get on with Brexit and move on to all the other things they care about. I share that frustration.”

Anger at the mounting scale of losses saw the Tory leader heckled as she gave a speech in Wales, with a man shouting: “Why don’t you resign? We don’t want you.”

Mrs May last night appeared to put the future of her party in the hands of Labour leader Jeremy Corbyn, by welcoming his offer to help her resolve the Brexit deadlock.

As counts terminated, Mrs May could only claim the election was “always going to be difficult” at a speech in Grimsby, one of the few areas in which the Conservatives enjoyed success.

She said: “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.

“As the party who has been in government for nine years, it was of course always going to be particularly difficult for us.

“But as we look at what happened, nobody was expecting that Labour was going to do as badly as they did.”

Foreign Secretary Jeremy Hunt on Saturday pointed the finger at “purist” Brexiteers in his party who he said were partially to blame for the Tories’ drubbing.

Asked who was responsible for the losses, he told reporters in Africa: “You can look at lots of different groups of people – you can look at Brexit purists in my party who have consistently refused to compromise and put Brexit in peril.

“You can for sure look at Government – I’m sure that there are things we could have done differently in the course of the negotiations. And you can look at the Labour Party who have played politics consistently.”

Local elections: net change in council seats after all 248 councils have declared Credit: PA Graphics

But it was a good night for the Liberal Democrats, whose leader Sir Vince Cable hailed the “best results we’ve had in the 40 years of our existence”.

Reflecting on several years of election losses, Mr Cable said the Lib Dems’ opposition to Brexit will help them in the upcoming European elections.

“We are clearly a major force, we are clearly the leading Remain party and we expect to do well on the basis of that,” he said on Saturday.

Lib Dem leader Sir Vince Cable Credit: David Mirzoeff/PA

Labour lost 63 seats when the party had expected to make gains, losing out to a surge in support for Lib Dems and Greens campaigning on an explicitly anti-Brexit ticket, as well as independent candidates.

Mr Corbyn left no doubt he saw the results as a demand for resolution of the Brexit impasse three years after the 2016 vote for EU withdrawal.

He told ITV: “I think it means there’s a huge impetus on every MP, and they’ve all got that message, whether they themselves are Leave or Remain – or the people across the country – that an arrangement has to be made, a deal has to be done, parliament has to resolve this issue. I think that is very, very clear.”