Another 249 Omicron cases were discovered in the UK as Plan B comes into action, according to latest figures.
Confirmed infections of the variant have climbed to 817, the Health Security Agency has said.
London has seen a sharp rise in cases of the Omicron variant with Lewisham and Newham among the boroughs most affected, health officials have revealed.
It comes as Boris Johnson announced Plan B was coming into force in the UK which includes Covid passes, face masks and work from home guidance.
During the press conference, Mr Johnson said the Omicron variant is “growing much faster” than Delta.
He added: “We are learning more every day... but since I last spoke to you it has become increasingly clear that Omicron is growing much faster than the previous Delta variant and it’s spreading rapidly all around the world.”
New variant figures were published on Thursday after Sajid Javid issued a stark warning Omicron cases could exceed 1 million by the end of this month.
In the House of Commons, the Health Secretary delivered a statement on the Omicron variant on Wednesday while Mr Johnson outlined the Government’s plan of action.
He said there are 568 confirmed cases of the Omicron variant but the estimated current number is “probably closer to 10,000”.
“Although there are only 568 confirmed Omicron cases in the UK we know that the actual number of infections will be significantly higher,” he said.
“The UK health security agency estimates that the number of infections are approximately 20 times higher than the number of confirmed cases, and so the current number of infections is probably closer to 10,000.
“UKHSA also estimate that at the current observed doubling rate of between two and a half and three days, by the end of this month, infections could exceed 1 million.”
