The capital's NHS Nightingale hospital is still on standby as the number of Covid-19 patients passes the peak set in the first wave.
The temporary hospital at the ExCeL in Custom House is currently empty but could be brought back into service, the NHS has confirmed.
A spokesperson said: “The Nightingale in London remains on standby and will be available to support the capital’s hospitals if needed.
“In the meantime, it is vital Londoners do everything possible to reduce transmission and cut the number of new infections, which otherwise inevitably result in more avoidable deaths.”
In April, the ExCeL in Western Gateway was converted into a hospital with 4,000 intensive care beds. It is run by Barts Health NHS Trust, which manages Whipps Cross, the Royal London and St Bartholomew’s hospitals.
In November, questions were raised as to whether it could be needed again. Keeping it in a “state of readiness” costs Barts £1.2million a month.
But England's hospitals now have more Covid-19 patients than during April's first-wave peak.
NHS England figures show there were 20,426 patients in NHS hospitals in England as of 8am today (Tuesday, December 29) compared to the 18,974 patients recorded on April 12.
The number of further lab-confirmed cases of coronavirus recorded in a single day in the UK also hit a new high of 41,385 as of 9am today, rising above 40,000 for the first time, according to government figures.
As of 8am on Christmas Eve at Barts hospitals, 486 in-patients had confirmed Covid-19. A total of 86 patients in intensive care were being treated for the virus.
There were 323 confirmed Covid-19 patients at Barking, Havering and Redbridge University Hospitals NHS Trust as of December 22. The trust has already postponed non-urgent services.
NHS bosses have described 2020 as possibly "the most challenging" in the service's 72 year history in a letter to trusts across the country.
The letter, dated December 23, details the NHS's priorities and the "critical" steps to take in order for staff to cope with the second wave and new strain of the virus.
In the letter, chief operating officer, Amanda Pritchard, and chief financial officer, Julian Kelly, tell trusts to plan for the use of extra facilities, including Nightingale hospitals.
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