Boris Johnson has urged people to keep faith in the coronavirus vaccines, after studies suggested that the Oxford-AstraZeneca jab may be less effective at preventing mild cases of the variant first detected in South Africa.
Speaking to reporters during a visit to a manufacturing facility in Derby, the British Prime Minister said the Government remains "very confident in all the vaccines that we're using".
"I think it's important for people to bear in mind that all of them, we think, are effective in delivering a high degree of protection against serious illness and death, which is the most important thing.
"I've no doubt that vaccines generally are going to offer a way out.
"With every day that goes by, you can see that medicine is slowly getting the upper hand over the disease."
His comments come after Professor Shabir Madhi, who led the latest trial of the Oxford-AstraZeneca vaccine against the South African variant, told the BBC's Radio 4 Today programme that the jab may only be 10 per cent effective against the variant.
South Africa will suspend the use of the vaccine - which New Zealand has pre-purchased millions of doses of - over concerns it may not be fully protective against a new variant.
The move came on the back of a new analysis, to be released before peer-review, that found the Oxford-AstraZeneca's ChAdOx1 vaccine provided only minimal protection against mild-moderate Covid-19 infection from the B.1.351 (South Africa) coronavirus variant.
The variant, first identified in South Africa in mid-November, has since been confirmed in cases in New Zealand's borders.
The analysis, carried out by the Wits Vaccines and Infectious Diseases Analytics (VIDA) Research Unit which runs the Oxford Covid-19 vaccine trial in South Africa, involved about 2000 volunteers, with a median age of 31.
Meanwhile a small United States study tracking 20 vaccine recipients has found the Pfizer/BioNTech Covid-19 jab is effective against the coronavirus variant that emerged from South Africa.
Some 147 cases of the South African variant have so far been identified in the UK, but experts warn these are likely to be the "tip of the iceberg" due to the fact they are the result of random checks on 5 to 10 per cent of all positive tests.