Boris Johnson is worried a 'vaccine busting' mutant Covid strain could enter the UK
Borders have been shut as part of emergency measures to protect Britain from new variants of the virus found abroad.
Speaking at a No10 coronavirus briefing this evening, the Prime Minister said: "We've made such progress with the vaccine, what we don't want to see is that hard work undone by a new variant that is vaccine-busting, as it were."
Terrifying new variants of Covid, which are significantly more transmissible that the original strain of the virus, have been located in South Africa and Brazil.
Just before Christmas flights to and from South Africa were suspended to try and keep the strain out of the UK.
Another strain from Brazil was discovered earlier this week, with the Government taking action to ban flights from the country and most other South American nations.
Tonight Mr Johnson went further by shutting travel corridors in a bid to protect Britain.
Anyone arriving into Britain from 4am on Monday will be required to have proof of a negative Covid test 72 hours prior to travel and must immediately isolate on arrival.
Over 3.2million people across the UK have now been vaccinated, including almost 45 percent of over-80s, and almost 40 percent of care home residents.
More to follow...