Omicron cases have risen as 448 new cases of the variant have been discovered in the UK.
There are 1,265 total cases in the country after the latest figures come in.
UK Health Security Agency released the latest figures with 443 cases in England, one in Scotland and four in Wales.
It comes as the UK recorded a total of 58,194 cases and 120 deaths.
This is the highest daily cases tally since January 9 at the height of the third wave, when 59,937 cases were recorded.
The UK is expected to face one million Omicron cases by the end of December, according to experts.
However, the Health Security Agency said boosters provide 70-75% protection against the variant.
The UKHSA said in a statement: “It is projected that if current trends continue unchanged, the UK will exceed one million infections by the end of this month.”
It added: “The preliminary data showed effectiveness against the new variant appears to increase considerably in the early period after a booster dose, providing around 70-75% protection against symptomatic infection.
“Due to the early nature of the findings, all estimates are subject to significant uncertainty and are subject to change.”
The startling figures have been revealed after Nicola Sturgeon issued a stark warning about the Omicron variant.
Scotland could see a “tsunami of infections” from the new Omicron variant, she said.
“The fact is, we do face a renewed and very severe challenge in the face of of the new Omicron variant,” she said at a briefing in Edinburgh.
“To be blunt, because of the much greater and faster transmissibility of this new variant, we may be facing – indeed we may be starting to experience – a potential tsunami of infections.”
Coronavirus infections have increased in England over the last two weeks, new data suggests.
Around 891,500 people in England had Covid – the equivalent of around one in 60 people – in the week ending December 1, according to ONS estimates.
