British Prime Minister Boris Johnson welcomed the news that the World Health Organization recommended on Wednesday the Oxford-AstraZeneca coronavirus vaccine for use globally by all adults after some countries have questioned its efficacy.

Earlier this week, South Africa said it would put on hold the use of AstraZeneca's COVID-19 shot in its vaccination programme after data showed it gave minimal protection against mild-to-moderate infection caused by the country's dominant coronavirus variant.

"It was good to see the World Health Organization today confirm its support for the Oxford-AstraZeneca vaccine for use in everyone over the age of 18, and obviously over the age of 65," Johnson told a press conference.