Another 90 cases of the new Omicron COVID variant have been reported in the UK, taking the total to 336.
This compares with a total of 86 new cases reported on Sunday.
The UK Health Security Agency said 64 of the latest cases were in England, 23 in Scotland and three were identified in Wales. There have been no Omicron cases in reported Northern Ireland so far.
Concern grows over how harmful Omicron could be
It comes as experts said there is increasing concern that Omicron is spreading more quickly than the Delta variant – and that there are probably more than 1,000 cases in the UK.
Professor Paul Hunter, from the school of medicine at the University of East Anglia, told BBC Breakfast that it is still “uncertain” how it would spread in the UK and how harmful it could be.
He added: “I think the early signs are that it will probably spread quite quickly and probably start outcompeting Delta and become the dominant variant probably within the next weeks or a month or so at least.
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“The big remaining question is actually how harmful it is if you do get COVID with this Omicron variant, and that’s the question that we’re struggling to answer at the moment.”
PM denies scientists’ allegations
Meanwhile, Boris Johnson has denied scientists’ allegations that introducing travel restrictions to slow the spread of Omicron is like “shutting the stable door after the horse has bolted”.
Visiting police in Merseyside, the prime minister said: “No, I think what we’re doing is responding to the pandemic.
“I don’t think we need to change the overall guidance and advice we’re giving about Omicron in this country.
“We’re still waiting to see exactly how dangerous it is, what sort of effect it has in terms of deaths and hospitalisations.”