Theresa May faced heckles and laughter from a live TV audience over the collapse of her election manifesto, as she refused to stop school cuts.

Members of the audience giggled when the Prime Minister when she said Labour’s figures “don’t add up” – apparently amused that it was the Conservative manifesto that had to be rewritten.

There was a shout of “you’ve clearly failed” when Ms May said, of school funding, “nobody can guarantee the real terms per funding increase”.

The Prime Minister also refused to say at what level a cap on social care costs would be set, or how many millions of pensioners would lose winter fuel payments.

It was the initial refusal to impose a care cap which led to a humiliating U-turn four days later after fierce criticism, abandoning a key plank of the manifesto.

Ms May also faced tough questions over big cuts to police numbers while she was Home Secretary and the state of the NHS after years of “efficiencies”.

One midwife from Devon protested at the “chronic underfunding” and told her: “I see a lot of efficiency savings that are actually cuts. I see hospitals closing.

“I see staff that are at their wits end because they cannot give the care that they want to give.”

Another questioner asked Ms May whether she feared her self-acclaimed reputation as “bloody difficult woman” was making people view the Conservatives as the “nasty party again”.

But it was the ridicule that greeted the Prime Minister’s answer on education funding that will have most alarmed her aides, on a night she seemed nervous and uncertain.

Nicola, a teacher and “mother-of-two” from West Yorkshire, told Ms May she was “incredibly concerned” by cuts, amounting to seven per cent according to the independent Institute for Fiscal Studies.

“These cuts are clearly unsustainable. Are you prepared to change your current plans to prevent further damage to our schools?”

The Prime Minister insisted the Tories would “put in further record funding”, but got into trouble when she quickly tried to turn the discussion to her plans for grammar schools.

Asked again about funding, she claimed: “Nobody can guarantee a real-terms per-pupil funding increase. I mean, the Labour party’s manifesto, we know the figures don’t add up,” – prompting the laughter and heckles.

Ms May also refused to say how many police officers the country needed, after the total was slashed from around 133,00 to just 124,000 on her watch.

And an elderly critic of the so-called “dementia tax” – who feared his family would have to sell his home to pay his care bills – asked her: “Why Prime Minister should my generation vote for you?”