A record number of daily coronavirus cases have been reported across the UK for the second day running, with 88,376 infections confirmed on Thursday, APA reports citing BBC.
England's chief medical officer, Prof Chris Whitty, said the Omicron variant could rise "incredibly fast", but its peak subside quickly due to boosters.
There was also a record for top-up vaccines with 745,183 third or booster doses being given on Wednesday.
Boris Johnson has urged people to use "caution" in the face of the variant.
But the prime minister insisted England was not being put into lockdown by stealth, after some of his own MPs had accused the government of putting hospitality under an "effective lockdown".
Meanwhile, the Queen has cancelled her traditional pre-Christmas lunch as a precautionary measure amid the surge of the Omicron variant.