The number of confirmed cases of the Omicron variant in the UK has risen to 14 this morning, after three more were confirmed in Scotland.
So far nine people have been identified with the mutant strain north of the border, along with five in England.
Today the head of the UK Health Security Agency, Dr Jenny Harries, said that there were a further 10 "highly likely" cases.
Scientists around the world are scrambling to find out if the variant, classified as "of concern" by the World Health Organisation (WHO), is more deadly or if it evades vaccines.
Scottish health secretary Humza Yousaf this morning said there are now five cases in the Lanarkshire area and four in NHS Greater Glasgow and Clyde - up from the six across the two areas announced yesterday.
Health officials have so far announced three cases in London, as well as one in Brentwood, Essex, and one in Nottingham.
Wales and Northern Ireland have yet to announce confirmed cases.
Dr Harries said there is a current period "of great uncertainty" in understanding the new Omicron variant.
She told BBC Breakfast the booster dose of vaccine will "we hope, to some extent, counter the potential drop in vaccine effectiveness we might find with this variant".
Asked whether the UK will see a return to work from home guidance, she said: "The whole point about the booster programme and the introduction of mandatory face mask-wearing in enclosed public spaces is exactly to try and avoid that because we've made huge progress, we have great defences and, in the background, the dominant strain in the UK at the moment is very definitely Delta.
"So these vaccines will help that, it will keep serious infection, serious disease and hospitalisations at bay, but we do need this time to try and understand the new variant, and we would much prefer that we have that precautionary approach and then take appropriate actions."
Boris Johnson will give a Downing Street press conference this afternoon after new measures took force to tackle the Omicron variant.
The Prime Minister will speak after a flurry of announcements over the weekend as scientists found 11 cases of the strain with more than 30 mutations in the UK - with more cases expected to follow.
He is expected to speak about the new compulsory face mask rules which took effect in England from 4am today.
Mr Johnson will urge people to get their booster vaccines after the rollout was extended to all over-18s and the gap between second and third doses halved to three months.
Asked if there was any connection between Omicron cases in Scotland and Cop26 or a recent South Africa rugby match, Mr Yousaf told BBC Good Morning Scotland: "There's nothing that links these cases or indeed the variant back to Cop26 or indeed the rugby match."
He added: "There's nothing that indicates these cases or this new variant has come via the rugby or Cop26 but that work of course is still ongoing ."
Asked if the Government might tighten up England’s rules even further in the next three weeks, minister Edward Argar said: "It's not something I'm anticipating."
But the PM’s spokesman did not rule out tighter travel rules, or tighter rules after the new restrictions are reviewed in three weeks' time.
No10 said Boris Johnson was not “planning” to adopt the plea for eight days’ isolation, but did not rule it out, saying the response would be kept under review.
