THE NHS is at a "watershed moment" and cannot deliver required levels of care within the current funding it receives, Health and Social Care Secretary Jeremy Hunt has been told.

NHS Providers - the trade body which represents NHSservices - had previously warned the health service was "not where it would want to be" heading into winter amid concerns over a bad strain of flu.

The warning comes after bosses at Musgrove Park Hospital, in Taunton, confirmed a number of planned operations had been cancelled.

Last week, medical director Dr Stuart Walker also said the hospital had seen record numbers of patients arriving by ambulance.

"We have been very busy at Musgrove over the last few weeks," he said.

"We have seen a 10 per cent increase in emergency department attendances compared with last year.

"We saw two records at Musgrove last week - 117 emergency admissions on Wednesday and 116 patients arriving by ambulance on Thursday."

Meanwhile a letter, written by NHSservices' chief executive Chris Hopson, calls for extra investment on a long-term basis - and help with the immediate financial impact of "exceptional winter pressures" - to address the "fragility of the wider NHS".

READ MORE: Number of planned operations cancelled at Musgrove Park Hospital

Mr Hopson said: "Despite planning for winter more thoroughly and extensively than before, it hasn't been sufficient. Rising numbers of flu cases and more respiratory illness have placed intolerable pressures on staff.

"The NHS is no longer able to deliver the constitutional standards to which it is committed. We need to be realistic about what we can provide on the funding available.

"If we continue to run the NHS at close to 100% capacity, day in day out, permanently in the red zone, it's not surprising that the service can't cope when we get a high, but entirely predictable, spike in demand."

Warning that failure to act would lead to targets moving further out of reach, he said: "There is so much at stake. We can fix this, but there must be no more delay. The ball is now firmly in the Government's court."

The three-page letter calls for the Government to commit to increasing the NHS budget to £153 billion by 2022/23 - a sum which the Office of Budget Responsibility said was needed given projected increased demand for services.

It read: "The Government now needs to set out how it will create the sustainable, long term, health and care funding settlement you have rightly called for.

"Given the urgency of this task, substantial progress needs to be made by Budget 2018."

Former Liberal Democrat minister Norman Lamb said the country had to be "honest" about how to give the NHS more funding.

His party has called for adding a penny in the pound on income tax.

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He said: "The clear message from NHS leaders is that the government must drop its sticking plaster approach to the health service.

"The gap between demand and resources in the NHS is growing each year, with tragic human consequences across the country.

"The stark reality is that the current winter crisis is just a taster of what is to come unless ministers get to grips with the long-term funding shortfall facing the health service."

A Department of Health and Social Care spokesman said: "The NHS was given top priority in the recent Budget with an extra £2.8bn allocated over the next two years, and was recently ranked as the best and safest healthcare system in the world.

"We know there is a great deal of pressure in A&E departments and that flu rates are going up, and we are grateful to all NHS staff for their incredible work in challenging circumstances.

"That's why we recently announced the largest single increase in doctor training places in the history of the NHS - a 25% expansion."