And it says health officials have work to do before the public can feel confident that plans to redesign services across the country are “not just a cover for cuts in services”.Amid growing strain on the NHS last month, No 10 aides appeared to brief against Mr Stevens, accusing him of a lack of “enthusiasm” in rising to the challenge.The head of the heatlh service then hit back in a hearing of the committee last month – suggesting Mrs May had been “stretching it” to say the NHS had been given more money than it asked for.Today a new report by the public accounts committee urges both sides to stop “bickering in public” – saying such actions do little to inspire confidence that patients are being put first.And MPs called for action to tackle severe financial problems and prevent long-term catastrophic failure.The report warns of an “alarming” deterioration in the finances of the NHS, with a “colossal” £2.5bn deficit in 2015/16, up from £859m the previous year.While some improvements have been shown in the current financial year, the number of trusts in severe financial difficulty has increased, despite help from a £1.8bn fund, and “repeated raids “on funds intended for investment, the report warns. Meanwhile, access to care is worsening, with worsening performance against Accident & Emergency targets, longer ambulance response times and a social care system which is now “unable to meet demand,” the report says.It also says health officials have much more to do before the public can feel confident that plans to redesign services across the country are “not just a cover for cuts in services”.The country has been split up into 44 areas, with NHS leaders told to deliver plans which will save £22bn by 2021 while helping to meet rising patient demand.Last week an analysis of draft plans showed proposals for swingeing bed cuts, which think tanks said was not realistic given the record levels of crowding in hospitals this winter.However, the King’s Fund also said politicians should not collude to stop closures of unsafe services, with radical changes needed in the way some services were run.Meg Hillier MP, chairman of the PAC, said: “The NHS as we know it is under threat from growing and unsustainable financial pressures.“Few trusts feel they have a credible plan for meeting the financial targets they have been set by Government.“At the same time, the Government seems unable to get its own house in order – plundering NHS investment funds to plug holes elsewhere, and falling out in public over its longer-term strategy.”Referring to the bitter disputes betweeen NHS England and Number 10, the report states: “We believe that the Department of Health, NHS England and No. 10 must work together in the best interests of patients.“The fact that key players running our NHS are bickering in public does little to inspire confidence that patients are at the heart of everyone’s priorities.”Ms Hiller said: “Contradictory statements about funding from the Prime Minister and head of NHS England are an insult to taxpayers who deserve an honest, grown-up conversation about future finance and service provision.”She said the Government was ignoring “mounting evidence” that its plans were simply not “up to the job”.“It is inconceivable the Government would allow a catastrophic failure in the NHS and we expect it to take targeted action now to support NHS bodies facing severe financial problems,” the MP said, warning that a “sticking-plaster approach is not sustainable.”Chris Hopson, chief executive of NHS Providers, said: “This report conveys in stark detail the gravity of the challenges facing the NHS – it’s the latest in a long line of independent reports to conclude the financial situation is unsustainable. It is a chastening and much-needed reality check. We welcome the PAC’s clear endorsement of the concerns we have raised.”Cllr Izzi Seccombe, from the Local Government Association said: “We cannot have a sustainable NHS without a sustainable social care system – the two go hand in hand.“With social care facing a funding gap of £2.6 billion by 2020, it is vital that the Government properly funds social care. Without this, the NHS will continue to suffer.“As we have recently shown, council tax raising powers announced by government will not bring in enough money to fully protect the services which care for elderly and vulnerable people today and in the future. The social care funding crisis needs a long-term, sustainable solution, not short-term fixes.A Department of Health spokesman said: “We are united behind the ambition to make the NHS the safest, highest-quality healthcare system in the world – which also means ensuring financial sustainability for the future, and the hospital sector’s financial position has now improved by £1.3 billion compared to this time last year, with 44 fewer Trusts in deficit.”An NHS England spokesperson said: “The PAC are right to highlight the genuine pressures facing the NHS, but fortunately there is in fact fundamental agreement on the action now needed. To that end, the NHS Delivery Plan being published at the end of March will clearly set out the NHS’ realistic and agreed game plan for the next two years. “Bickering in public” between the Prime Minister and the head of the NHS is an insult to taxpayers when an urgent plan is needed to prevent “catastrophic failure” of services, MPs have said.The influential Public Accounts Committee has lambasted Theresa May and NHS chief executive Simon Stevens – and urged them to instead focus on an “alarming” deterioration in health service performance.The damning report also warns that the social care system is now overwhelmed by demand, amid “extreme pressures on funding.” NHS England boss Simon Stevens appearing on the BBC1 current affairs programme, The Andrew Marr ShowCredit:Jeff Overs/BBC It is inconceivable the Government would allow a catastrophic failure in the NHS and we expect it to take targeted action now to support NHS bodies facing severe financial problemsMeg Hillier MP Want the best of The Telegraph direct to your email and WhatsApp? 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