British Prime Minister Boris Johnson (L) visits a vaccination center in Aylesbury, Britain, Jan. 3, 2022. (Andrew Parsons/No 10 Downing Street/Handout via Xinhua)

Britain's National Health Service (NHS) will be under "considerable" pressure in the coming weeks amid the wave of the highly transmissible Omicron variant, British Prime Minister Boris Johnson said Monday.

"No question Omicron continues to surge through the country," Johnson said at a vaccination centre. "I think we've got to recognize that the pressure on our NHS, on our hospitals, is going to be considerable in the course of the next couple of weeks, and maybe more."

Johnson said Omicron appears "plainly milder" than previous variants, but it would be "folly" to say the pandemic is over. He urged people to take a test before "meeting someone you don't usually meet" and to get first, second and third vaccine doses where possible.

Britain reported another 157,758 coronavirus cases in the latest 24-hour period, bringing the total number of coronavirus cases in the country to 13,422,815, according to official figures released Monday.

Britain also reported a further 42 coronavirus-related deaths. The total number of coronavirus-related deaths in Britain now stands at 148,893, with 11,918 COVID-19 patients still in hospital.

Cases and deaths data on Monday only included England and Scotland.

More than 90 percent of people aged 12 and over in Britain have had their first dose of vaccine and more than 82 percent have received both doses, according to the latest figures. More than 59 percent have received booster jabs, or the third dose of a coronavirus vaccine.

To bring life back to normal, countries such as Britain, China, Germany, Russia and the United States have been racing against time to roll out coronavirus vaccines.