A decade of austerity helped the UK to prepare for the Covid pandemic, David Cameron and George Osborne have claimed.

Speaking during the official Covid inquiry on Monday, Cameron “defended” massive cuts to public services delivered while he was prime minister, saying they were crucial for the UK’s response to the Covid pandemic.

“Your health system is only as strong as your economy because one pays for the other,” he said.

The claims have sparked criticisms that Cameron is “in denial” about the impact of his policies.

Between 2010 and 2015, under Cameron’s leadership, the coalition government announced the biggest cuts to state spending since the Second World War. It aimed to reduce the UK’s deficit and led to an estimated half a trillion pounds less being spent on public services, according to a study from the Progressive Economy Forum.

“I will absolutely defend the record of the government in both getting control of the finances and increasing funding for the health service at the same time,” said Cameron in response to a witness statement from former health secretary Jeremy Hunt.

Hunt’s statement said that he raised “considerable concerns about the structural problems within NHS capacity and the workforce and funding”.

Cameron’s rebuttal continued: “If you lose control of your debt, and you lose control of your economy, you end up cutting the health service. And what I think what's needed to prepare for a pandemic is, first of all, you've got to have that overall economic capacity.”

At the time of austerity measures, the government said NHS spending was “ringfenced”. But the health service’s funding did not rise with inflation between 2010 and 2015, and areas such as social care received large cuts, further impacting the NHS.

Referencing the healthcare charity the Nuffield Trust’s 2015 annual statement – which stated that “slowing improvement in some areas of quality combined with longer waiting times and our ongoing austerity suggests the NHS is heading for serious problems” – the inquiry counsel asked Cameron whether he accepted that the government was repeatedly warned about growing pressures on the NHS.

“Of course, there were pressures on the NHS,” Cameron responded. “But there are always pressures on the services, and our job was to try and sort out the economy, which we did.”

Cameron also rejected findings from scientists whose report – heard at the inquiry on Friday – found that health inequalities increased during Cameron’s time in office. Michael Marmot and Clare Bambra found that almost no emergency planning reports referred to health inequalities.

“That conclusion is to look a lot at austerity and what have you. I'm not sure that figures back that out,” said Cameron.

Cameron rejected that “cuts to public health budgets tended to be largest in the most deprived areas, and that as a result, local authorities working with the most vulnerable populations face the biggest challenges in carrying out their public health function”.

Responding to Cameron's comments, the general secretary of the Trade Union Congress, Paul Nowak, said: “David Cameron is in denial about the huge damage caused by his austerity policies – both to public services and the UK economy.

“The evidence is clear that the cuts he imposed massively damaged the readiness and resilience of our public services. And they shredded our social security safety net - leaving millions vulnerable.

“We must learn the lesson that cuts have costs. And we must strengthen our public services and safety net so that we are never left exposed in the same way again.”

The inquiry also saw a witness statement from Cameron’s chancellor, George Osborne.

It said: “I have no doubt that taking those steps to repair the UK's public finances in the years following the financial crisis of 2008/09 had a material and positive effect on the UK's ability to respond to the Covid-19 pandemic.”

“Reducing the deficit and placing debt as a percentage of GDP on a downward path was also essential to rebuild fiscal space to provide scope to respond to future economic shocks.”

Osborne will provide evidence to the inquiry on Tuesday.

Cameron also told the first module of the Covid-19 inquiry, which is seeking to explore the UK’s preparedness for the pandemic, that he was “desperately sorry” about the loss of life.

“I’ve tried to be frank about the things that were missed…the thing I struggle with is why they were missed,” he said.

He admitted that “it was a mistake” to have mainly prepared for a flu pandemic, rather than a coronavirus pandemic.

Cameron left the inquiry, which is taking place in west London, to heckling from the public. “Shame on you,” one person shouted.

The inquiry continues.