Video report by ITV News UK Editor Paul Brand
Forced quarantine is expected to be introduced by the government for those arriving at airports to shield against new variants of Covid-19, ITV News understands.
Plans are still to be finalised, according ITV News UK Editor Paul Brand, with a meeting of ministers on Tuesday set to decide finer details.
Disagreements remain over who the quarantine would apply to - whether it would affect anyone arriving at the border or only those from high-risk countries.
Under the plans, incomers would be required to stay in a hotel for ten days without leaving and at their own expense.
Paul Brand details what we know of the plans under discussion
Plans come as the government reported a further 610 people had died within 28 days of testing positive for Covid-19, bringing the UK total to 97,939.
The government also said that, as of 9am on Sunday, there had been a further 30,004 lab-confirmed cases of coronavirus in the UK.
But in better news, a new daily record of almost half a million people received their first dose of the Covid vaccine across the UK on Saturday, bringing the total to 6.4 million.
And the number of new Covid infections is at its lowest since the week before Christmas.
England, however, is a "long, long, long way" off being able to lift Covid-19 restrictions, according to the health secretary.
Matt Hancock said there was evidence that restrictions in place were having an impact while the vaccination programme was making "brilliant progress".
Three quarters of all those over 80 in the UK had now been vaccinated, with a similar number of those in care homes, he said.
As of the end of Friday, more than 5.8 million people had had at least one dose of the Covid jab, with a record 478,248 getting the vaccine in a single day.
However, he said that case numbers were "incredibly high", the death toll each day is still "far too high" and the NHS remained under "enormous pressure".
"There is early evidence that the lockdown is starting to bring cases down but we are a long, long, long way from being low enough because the case rate was incredibly high," he told Sky News's Sophy Ridge on Sunday programme.
"You can see the pressure on the NHS - you can see it every day."
Asked on the BBC when coronavirus restrictions could be lifted, Mr Hancock said he did not "yet know the answer".
Professor Linda Bauld, professor of public health at Edinburgh University, stressed that "public health measures remain the same" despite the "huge progress" made in vaccinating 5.8 million people across the country.
"The first dose is not protective for a few weeks and even then full protection is not provided until people have had their second dose," she told ITV News.
Prof Bauld echoed comments made by deputy chief medical officer Professor Jonathan Van-Tam when he warned in a newspaper article of the Meanwhile, the deputy chief medical officer for England, Professor Jonathan Van-Tam, has called on those people who have been vaccinated to keep following the rules on social distancing.
Writing in The Sunday Telegraph, Prof Van-Tam said it was still not known if people who had received the jab could still pass on the virus to others, even though they were protected from falling ill themselves.
"If you change your behaviour you could still be spreading the virus, keeping the number of cases high and putting others at risk who also need their vaccine but are further down the queue," he said.
Speaking to ITV News, Prof Bauld explained: "It's also important that we recognise that just because someone has received the vaccine and even when full protection is there, what we don't know is whether that prevents them from picking up the virus and giving it to someone else and that's because the original trials didn't study that, so we have to be very cautious that that is still a risk."
She continued that people must not get complacent over lockdown rules.
"It's a very fragile situation," Prof Bauld said.
"You can see that the prevalence and incidence of the disease in the population is beginning to decline even though we have so many people in hospital and the deaths, those rates will not go down for some time.
"So we have to not be complacent.
"I think it's challenging for government, the messaging - they really want to emphasise the positive, which is the rollout of the vaccine, but they actually have to have two messages aligned with each other: 'vaccine rollout is going well, please take up the offer if you're invited', and 'in the meantime the public health measures remain the same and it's very important that everyone follows the guidance'."
Mr Hancock said that so far there were 77 known cases of the South African variant in the UK and nine of the Brazilian.
He said that all the cases of the South African variant were linked to travel.
"There is not what we call community transmission where you find a case that you can't find the link back to travel. At the moment it is all linked to travel," he told BBC One's The Andrew Marr Show.
He said the new variants had been identified because both Brazil and South Africa had "decent-sized" genomic sequencing programmes but other countries were less well covered.
"The new variant I really worry about is the one that is out there that hasn't been spotted," he told Sky News.
"There's probably those elsewhere that simply haven't been picked up because the country doesn't have that genomic sequencing service."
A further 32 vaccine sites are set to open across the country this week including one at the museum made famous as the set of hit TV series Peaky Blinders.
The sites include the Black Country Living Museum in Dudley, which featured in the long-running TV show, a racecourse, a football stadium and a former Ikea store.
Prof Van-Tam meanwhile has hit back at doctors who have criticised the decision to extend the gap between the first and second doses of the vaccine to 12 weeks.
The British Medical Association has written to the chief medical officer for England urging a rethink, saying that in the case of the Pfizer-BioNTech vaccine a maximum gap of six weeks had been mandated by the World Heath Organisation (WHO).
Prof Van-Tam said that extending the gap was the quickest way to get a first dose to as many people as possible, as quickly as possible.
He said: "But what none of these (who ask reasonable questions) will tell me is: who on the at-risk list should suffer slower access to their first dose so that someone else who's already had one dose (and therefore most of the protection) can get a second?"
Mr Hancock also told Sky News that while he hoped schools in England could reopen by Easter, it would depend on the levels of infection in the community at that time.
"We have got to look at the data, we have got to look at the impact of the vaccination programme," he said.
"The Education Secretary (Gavin Williamson) has said that we will ensure schools get two weeks' notice of return. I don't know whether it will be then or before then. We have got to watch the data."
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