The UK has recorded 50,091 new COVID-19 cases and 160 more coronavirus-related deaths in the latest 24-hour period, government data shows.
It is the first time since 21 October that new cases have been above 50,000 - on that day 52,009 new infections were announced.
The latest figures compare with 47,240 infections and 147 fatalities reported on Thursday, while this time last week 44,242 cases and 157 deaths were recorded.
It comes as Europe has recorded its first case of a worrying new COVID variant after it was detected in Belgium. It has previously been identified in other places including South Africa, Botswana, Hong Kong and Israel.
The UK has so far not reported any cases of the variant, named B.1.1.529, but Health Secretary Sajid Javid earlier said it was highly likely it has now spread beyond southern Africa.
He warned the new strain could be more transmissible than the Delta variant and there is a "possibility it might have a different impact on individuals" who get the virus.
He said the UK remains in a "strong position" due to the high vaccination take-up but said the new variant has an "unusually large number of mutations".
The Department of Health and Social Care said: "The variant includes a large number of spike protein mutations as well as mutations in other parts of the viral genome.
"These are potentially biologically significant mutations which may change the behaviour of the virus with regards to vaccines, treatments and transmissibility. More investigation is required. No cases have been identified in the UK."
The UK government has added South Africa, Botswana, Lesotho, Eswatini, Zimbabwe and Namibia to the UK's travel red list amid the concerning new strain. And flights from these nations to the UK have been suspended until 4am on Sunday until hotel quarantine is up and running.
Passengers arriving in the UK from these countries from 4am on Sunday will be required to book and pay for a government-approved hotel to quarantine for 10 days. Downing Street has urged anyone who has arrived from these countries recently to get tested.
Meanwhile, the weekly R number in England is estimated to have risen to between 1.0 and 1.1.
The reproduction figure, from the UK Health Security Agency (UKHSA), means that for every 10 people with coronavirus they will, on average, infect between 10 and 11 others.
The pandemic therefore appears to be growing in England, as 'R' was estimated to be between 0.8 and 1.0 last week.
There are currently 7,633 COVID patients in UK hospitals, including 925 in ventilation beds.
Another 23,579 people have had their first dose of a COVID vaccine on Thursday, taking the total to 50,875,712.
Also, 22,823 had their second jab, meaning 46,255,081 have had two doses in the UK.
There were 396,081 more booster or third doses administered on Thursday, taking the total to 16,779,656.