Every area has been ordered to draw up meaures to save £22bn and reorganise health services in order to meet rising demand from an ageing population.

But new documents suggest that the proposals could result in the loss of more than 17,000 staff by 2020 – including 7,300 nurses and midwives.

Last night senior nurses said the implications for safety were “truly frightening” with widespread shortages of staff already in overstretched hospitals.

The forecasts, seen by Health Service Journal, also reveal that the plans rely on a dramatic reversal in trends which have seen casualty units under unprecedented pressure.

While A&E attendances across England have risen by 4.5 per cent and emergency admissions by 3.5 per cent in the past 12 months, the plans rely on a 4.2 per cent fall in attendances, and a 0.8 per cent drop in admissions.

Health authorities across England have been ordered to draw up 44 “sustainability and transformation plans” (STPs) to tackle rising pressures on the health service.

The controversial measures will see swingeing bed cuts in many parts of the country, and widespread closures of Accident & Emergency departments.

Officials insist that the changes will improve patient care, by shifting investment into GP and community services.

The analysis by HSJ examined finance, workforce and efficiency forecasts supplied alongside the STPs.

The data – from a sample of one in four STPs – suggests that savings rely heavily on job cuts, with a 2.3 per cent fall in registered nurses, and a 1.6 per cent reduction in all jobs.

Applied across England, it would mean reducations of around 17,300 staff in total, including 7,300 nurses, midwives and health visitors.

While the forecasts set out plans to boost GP numbers, the time taken to train such staff mean a time lag between cuts to hospital staff, and any significant increase in family doctors.

The documents also set out plans to increase the number of GP “support staff.” Health officials said this might include some nurses.

Senior doctors have warned that the NHS is currently battling the worst winter crisis in its history.

Latest figures show that in the first week of January, almost half of NHS trusts declared major alerts, with fears that the situation may worsen, amid rising levels of flu.

Tom Sandford, Royal College of Nursing drector of England, said reductions in nursing posts would have “truly frightening” implications for patient safety.

“Nursing staff make up the biggest proportion of the NHS workforce. There are already 24,000 vacant nursing posts across the UK,” he said.

“We have been hearing from members how the current situation is the worst that many have ever experienced. The situation cannot be allowed to worsen.”

Nigel Edwards, chief executive of think tank the Nuffield trust, suggested the plans were an unrealistic attempt to balance the books.

“Demand has been going up by around four per cent a year for around two decades and the demography of the next three to five years is characterised by the population ageing rapidly and growing – with a bulge in the group that uses healthcare most,” he said.

“These are very bold, if not heroic assumptions,” he said. “The question is whether this is achievable – and if it was, would it really be palatable?”

An NHS England spokesman said the planning process was still ongoing.

He said health officials expected to see a rise in the total number of nurses employed, with an expansion in the numbers employed in community and primary services.

“We are confident that a growing NHS will see more qualified nurses employed across England,” the spokesman said.