Hospitals are under mounting pressure with routine surgery cancelled and plans to move critically patients hundreds of miles for treatment.
Cancer operations could be shelved in the capital as the NHS creaks under the strain of Covid-19, it was reported.
With London hospitals facing a “dire situation”, coronavirus stricken patients could be taken to the Midlands and the West Country, where demand for beds is yet to peak, under “pairing” arrangements.
Medics warned that patients were getting younger, with people as young as 30-years-old in intensive care units.
New Covid cases in the UK surged above 50,000 for the fifth day in a row on Saturday, with a record-high of 57,725 lab-confirmed cases and 445 deaths.
NHS Providers chief executive Chris Hopson said: “At the moment hospitals are doing a great job creating extra surge capacity in London and the South East to treat the critically ill.
“If it gets more difficult, we will find other ways to treat people within the region but we know there are some patients that can be moved to where the pressure is slightly less, for example the South West and Midlands.”
He later called for “appropriate restrictions” as he expressed alarm at hospital admissions in the past eight days.
“What we’ve seen since Christmas Day, which was just eight days ago, is a very, very rapid rise in the number of patients who are in hospital with Covid-19,” he told Sky News.
“So we had 17,700 patients in hospitals on the 25th of December, we’ve now got 23,500 as of yesterday, so that’s a 5,800 increase.
“That’s something like 12 extra full hospitals, full of Covid patients, a 33% increase in just eight days.
“So you can imagine why people in the NHS are worried about how quickly this virus is spreading.
“So yes, everybody in the NHS is really very clear that we need to have appropriate restrictions in place.”
Dr Shondipon Laha, an intensive care consultant in Lancashire, told the Sunday Telegraph: “The situation in hospitals is dire in London, but the situation around the country is only a few weeks behind and London is not at its peak yet.
“If you start seeing London overwhelmed it can happen everywhere else quickly.”
One nurse at the Whittington Hospital in North London, said some patients were being left in corridors and others were being held in ambulances for up to three hours because of a lack of beds.
They said: “I’m worried about patient safety because if these little things are happening now when we’re short and it’s busy, it’s only going to get worse… It’s not having enough nurses to care for patients, patient safety is being affected.
“Some are in corridors, being looked after in makeshift areas, makeshift wards have been created for Covid patients, and ICUs are running out of space.”
ICU nurse Suzanne Barke told the Sunday Times: “This was my worst time as a nurse. The patients are getting younger.”
Dr Alison Pittard, the dean of the Faculty of Intensive Care Medicine, said younger people were being affected, with patients as young as 30 in intensive care.
“We are still seeing older patients, we are treating the whole age range so that’s not changed,” she told BBC’s Andrew Marr Show.
“But it does affect younger people, so just because you are not in the older age bracket doesn’t mean you are immune to this disease.
“I have heard reports of people as young as 30, 35, being in intensive care with Covid.
“Obviously the younger you are the better your body is at coping with the disease but still younger people will die from Covid because we never know how people are going to respond to it.”
Dr Pittard said the NHS was trying to continue with its other services and treat patients while also dealing with the second coronavirus wave.
She said: “One of the things I would like to tell the public is that if you have any concerns, whether it is about Covid or not, you must seek advice and help.
“We plan to continue as much normal activity as possible but of course some of the non-urgent stuff will still need to be postponed.”
Dr Pittard warned that staff were “very, very tired” compared to the first stages of the pandemic.
She said: “We can’t just create staff overnight. We can get more drugs. We can get more beds and equipment but we can’t just get more staff, so that is the real concern this time around.”
Boris Johnson signalled that Covid restrictions were likely to get tougher – despite vaccines “coming down the track in their tens of millions”.
“What we are doing now is using the tiering system, which is a very tough system… and, alas, probably about to get tougher to keep things under control,” he told the BBC’s Andrew Marr Show.