Video report by ITV News Political Correspondent Shehab Khan
Boris Johnson has signalled that England's current Covid tier system could be tightened, with tougher measures likely to come in.
A new Tier 4 was introduced initially in London and the south-east two weeks ago and now covers the majority of England, but despite these tough measures, coronavirus cases continue to soar.
Scotland, Wales and Northern Ireland are all in lockdowns, since health is a devolved matter.
Labour leader Sir Keir Starmer has called on the prime minister to bring in new national restrictions within the next 24 hours, rather than hint that he will do so soon.
On Sunday, a further 54,990 people have tested positive for Covid-19 in the UK in the past 24 hours, according to the Department of Health. This is the sixth day in a row that there were more than 50,000 new cases of Covid-19 in the UK recorded in the past 24 hours, which brings the total number of cases in the UK to 2,654,779.
The spiralling numbers of cases are linked to a new variant which is much more transmissible that the coronavirus we have been living with since the spring.
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Speaking on BBC One's The Andrew Marr Show, the prime minister, suggested current anti-Covid measures were likely to get tougher.
"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," Mr Johnson said.
"But, we will review it."
Mr Johnson said a mass vaccine programme was the way out of the tiering system.
"We have the prospect of vaccines coming down the track in their tens of millions.," Mr Johnson said.
"And that, I think, is something that should keep people going in what I predicted, back on your show in in October, will be a very bumpy period right now.
"It is bumpy and it's going to be bumpy."
Mr Johnson's warnings of tougher measures were echoed by the government's former chief scientific advisor and current member of the Scientific Advisory Group for Emergencies (Sage), Professor Sir Mark Walport, said it was "pretty clear" tougher restrictions were needed.
Not only this, but he said the restrictions must be obeyed.
"It is thinking about breaking essentially every possible route of transmission we possibly can," Sir Mark said.
"Those are the things that are absolutely necessary and it is pretty clear we're going to need more."
He continued it would be difficult to keep the new variant under control without "much tighter" social distancing measures.
Sir Mark told Andrew Marr: "It's clear that this new variant is transmitting more readily, it's transmitting more readily in younger age groups as well.
"It's important to note that it doesn't appear to cause worse disease or that it's going to be more resistant to the effects of the vaccine, but it is going to be very, very difficult to keep it under control without much tighter social distancing measures."
He appeared to indicate that one of the next steps could be to close schools.
"We know that transmission occurs within schools," Sir Mark said.
"We know that a person between 12 and 16 is seven times more likely than others in a household to bring the infection into a household.
"And we know that there was a small dip in the amount of transmission in school children after the half term, which then went up again when they went back."