But it is still well below the second wave peak of 4,134 admissions on January 12, despite more record case numbers being reported.
Government figures show a further 189,846 lab-confirmed Covid-19 cases had been recorded in the UK as of 9am on Friday, another new record for daily reported cases.
It comes after new Office for National Statistics (ONS) data showed an estimated 2.3 million people in the UK had Covid-19 in the week ending December 23.
This is up from 1.4 million in the week to December 16 and the highest number since comparable figures began in autumn 2020.
Meanwhile, separate NHS England data showed 24,632 staff at NHS hospital trusts were ill with coronavirus or having to self-isolate on Boxing Day, up 31% from 18,829 a week earlier and nearly double the 12,508 at the start of the month.
Matthew Taylor, chief executive of the NHS Confederation, said the NHS is facing a “perfect storm” of rising Covid hospital admissions and illness alongside increasing numbers of frontline workers being off sick.
“The NHS is putting in plans to step up once again for patients with the new Nightingale surge hubs, extra support from community services and virtual wards, but there is no doubt the whole system is running hot,” he said.
“While the Government seems determined not to increase restrictions in England, it is vital we all behave in ways that will not exacerbate an already dangerous situation.”
The scale of rising staff absences has led to political calls for an emergency Government Cobra meeting to be convened “without delay” by the Prime Minister to “thrash out a comprehensive rescue plan”.
Liberal Democrat health spokeswoman Daisy Cooper said the health service was being “stretched to breaking point”, adding: “Our NHS is in desperate need of support. The Government must give this crisis the attention it deserves.”
Across the UK, there were 1,915 Covid-19 hospital admissions on Monday (December 27) – up 62% week-on-week and the highest number since February 8, according to Government figures.
There were 11,918 people in hospital in the UK with Covid-19 on Wednesday (December 29), up 44% week-on-week and the highest number since March 2.
In England, there were 12,395 people in hospital with Covid-19 as of 8am on New Year’s Eve, according to figures from NHS England.
This is up 68% from a week earlier and is the highest number since February 25.
NHS England national medical director Professor Stephen Powis said the health service is setting up the Nightingale surge hubs at hospitals across the country and recruiting thousands of nurses and reservists.
He added: “We don’t yet know the full scale of rising Omicron cases and how this will affect people needing NHS treatment but, having hit a 10-month high for the number of patients in hospital with Covid while wrestling with sharply increasing staff absences, we are doing everything possible to free up beds and get people home to their loved ones – and in the last week hundreds more beds were freed up each day compared to the week before.
“The NHS is on a war footing, and, while staff remain braced for the worst, with Covid absence for NHS staff almost doubling in the past fortnight, keeping as many colleagues as possible at work on the front line and minimising absence, will be essential in the next few weeks.”
Prof Powis also urged people to get vaccinated, with 397,554 booster and third doses of Covid-19 vaccine reported in the UK on Thursday.
More than 33.9 million booster and third doses have now been delivered in the UK, with around 64% of all adults having now received a booster or third dose.
The ONS figures, published on Friday, also showed that around one in 25 people in private households in England had Covid-19 in the week to December 23, up from one in 45 in the week to December 16.
One in 25 is the equivalent of about two million people and is the highest number since the ONS began estimating infection levels for England in May 2020.
In London, around one in 15 people were likely to test positive for Covid-19 in the week to December 23, the highest proportion for any region in England.
The ONS said that in Wales around one in 40 people are estimated to have had Covid-19 in the week to December 23, equalling the previous record set in October.
In Northern Ireland, the latest estimate is also one in 40, equalling the record set in mid-August, and for Scotland, the latest estimate is one in 40 and the highest since records began.
Meanwhile, ministers have been warned they must be ready to apply restrictions “at pace” as the NHS puts itself on an emergency footing to deal with a possible surge in Covid-19 patients.
Chris Hopson, chief executive of NHS Providers, said trust leaders recognise that the UK Government’s threshold for introducing extra measures in England “hasn’t been crossed yet” but that additional capacity is being created in case hospital pressures increase.
In Scotland and Wales, nightclubs are closed to New Year’s Eve partygoers, and restrictions have been placed on hospitality.
But in England, ministers have opted to forgo measures beyond the UK Government’s Plan B, which includes mandatory Covid passes for large events, increased mask-wearing in public places and work from home guidance.
Mr Hopson, chief executive of the group which represents health trusts in England, said even if extra restrictions are put in place to control the Omicron variant, it will take two weeks to reduce the hospital admission rate.
He told BBC Radio 4’s Today programme: “It is the Government who sets the rules on restrictions, not the NHS, and we know that the Government has set a high threshold on introducing new restrictions.
“So, on that basis, trust leaders can see why the Government is arguing that, in the absence of a surge of seriously ill older patients coming into hospital, that threshold hasn’t yet been crossed.
“But we still don’t know if a surge will come, and indeed we are exactly talking about the preparations we are making for that surge right now.
“So, in terms of restrictions, I think we are in exactly the same place we’ve been for the past fortnight, which is the Government needs to be ready to introduce tighter restrictions at real speed should they be needed.”