Watch: COVID-19: UK records another 696 coronavirus-related deaths - the highest daily total since start of May
A further 696 people have died within 28 days of testing positive for Covid-19, the highest daily figure reported since 5 May.
The government said as of 9am on Wednesday there had been a further 18,213 lab-confirmed cases of coronavirus in the UK.
It brings the total number of cases in the UK to 1,557,007.
Separate figures published by the UK's statistics agencies for deaths where Covid-19 has been mentioned on the death certificate, together with additional data on deaths that have occurred in recent days, show there have now been 72,000 deaths involving Covid-19 in the UK.
It comes as scientists warned easing coronavirus restrictions over Christmas could lead to a third wave of the pandemic and another lockdown.
Prime Minister Boris Johnson has told families they must make a "personal judgment" about the risks of coronavirus to vulnerable loved ones when forming a Christmas bubble.
The prime minister urged the public to "think carefully" over the festive period, after it was confirmed that three households will be able to mix from 23 to 27 December.
The UK government and devolved administrations have agreed a joint plan to relax social distancing rules over the festive period, allowing friends and family to hug for the first time in months.
But a member of the government's Scientific Advisory Group for Emergencies (Sage) warned the planned easing of measures could lead to a third wave of the pandemic.
Another said that the risks people take at Christmastime could lead to more hospital admissions in January and potentially another lockdown.
Professor Graham Medley, an expert in infectious disease modelling at the London School of Hygiene & Tropical Medicine, said the relaxation of coronavirus restrictions at Christmas could lead to more people being admitted to hospital and further lockdown measures in the new year.
The Sage attendee told BBC Radio 4's Today programme: "I think we're in a process now whereby the population's risk of filling up the NHS is really being passed down to us as individuals.
"For other diseases like flu or hepatitis B, the government doesn't get involved in helping or determining what our risk is and it is really, I think, for this Christmas up to us as individuals and families to think about what our risks are and how we are going to mitigate them.
"I think it is inevitable that if a lot of people do take that risk, even if it is a small risk, then we will end up with a lot of people in hospital and potentially having to take measures in January to lock down again."
Prof Medley advised people to isolate before visiting relatives, to consider the amount of time they plan to spend with them, to remain "completely faithful" to any social bubble arrangements and to weigh up the risk of spreading Covid to those who are vulnerable.
But he said, even with mitigations in place, social interactions come with risks that "could play out very badly for some people".
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Andrew Hayward, professor of infectious diseases epidemiology at University College London, and a member of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), warned easing measures would lead to increased transmission and a possible "third wave" of infection.
"Effectively what this will be doing is throwing fuel on the Covid fire," the professor, who is also a Sage member, told BBC2's Newsnight on Tuesday.
He added: "With the vaccine on the way, if we are not very careful over Christmas we are really in danger of snatching defeat from the jaws of victory on this one."
It comes as the British Medical Association in England also warned easing of coronavirus restrictions over Christmas will "almost certainly" lead to a rise in the infection rate.
Additional reporting by Press Association