Downing Street has confirmed that David Cameron is getting personally involved in overseeing the NHS's response to expected pressures on casualty departments in England this winter.
The move comes amid warnings that accident and emergency (A&E) wards are facing a crisis because of increased demand for services and a shortage of doctors.
The College of Emergency Medicine said that more than half of specialist registrar posts in A&E have been left vacant over the past three years, with many doctors moving to other specialities or going abroad.
Meanwhile, the Department of Health confirmed that private hospitals have been asked how many beds they can provide to take pressure off the NHS this winter, but pointed out that this has been the regular practice every winter for at least 10 years.
The Financial Times reported that Mr Cameron was personally overseeing detailed contingency planning for NHS services this winter, amid Conservative fears that any rise in waiting times or delays in A&E treatment could be politically damaging for their party.
In response to the report, Mr Cameron's official spokesman told a regular Westminster press briefing: "Is the Prime Minister working very closely with the Secretary of State for Health on health matters with a particular focus around A&E? Absolutely, he is doing that."
Asked whether it was right that the PM had demanded weekly updates on A&E admissions, the spokesman said: "Yeah, he does want to be - and he continues to be - up to date with the very latest NHS performance statistics, including the A&E statistics."
The PM's spokesman said the Government had already announced £500 million of additional funding over two years for A&E departments facing the greatest pressure.
He added: "Around 1.2 million more people are using A&E compared to three years ago. Over the recent period, A&E departments have been meeting the 95% performance measure of those waiting being discharged or admitted within four hours. Compared to 2010, average waiting times are down from 70 to around 50 minutes."
A Department of Health spokesman said: "Winter is always tough, but the NHS has never been more prepared.
"We are tackling both the short and long-term problems: transforming out-of-hospital care by expanding the role of GPs, joining up the health and social care system, and backing A&Es with £250 million to prepare for this winter.
"As part of their routine winter planning, NHS Trusts look at bed capacity, including what role, if any, the independent sector has to play - as they have done for at least a decade."
Cliff Mann, president of the College of Emergency Medicine, said that A&E departments had reached a "tipping point" because 383 of 699 specialist registrar posts in A&E had been left vacant over the past three years.
With each registrar expected to see 2,000 patients a year, the CEM said the shortfall had deprived hospitals of the capacity to see 766,000 emergency patients annually.
Mr Mann told The Times: "We've heard from all politicians that they are very concerned, but we're trying to change that concern into pragmatic and sensible decision-making. Part of the problem is that there are now a lot of semi-detached organisations to deal with.
"It's one thing to impress on the Department of Health, but you also have to make sure that NHS England agrees as well as the clinical commissioning bodies."
Writing in The Times, shadow health secretary Andy Burnham said: "The NHS stands on the brink of a dangerous winter in an even worse position than last year - with fewer nurses, fewer beds, a shortage of senior A&E doctors and social care support further reduced."
A Department of Health spokesman said: "There are nearly 4,100 more clinical staff working in our NHS than there were in 2010, but more needs to be done to tackle the historical shortages of medical staff in some specialties including A&E.
"That is why we have set up a specialist organisation called Health Education England with a clear set of priorities to increase the number of A&E doctors and the number of medical students choosing A&E as a career.
"Hospitals need to make sure that they have the right staff in place, including at night. Evidence shows that increasing consultant numbers in the evenings and overnight improves patient care in A&E and elsewhere in our NHS."