The World Health Organization (WHO) said it would be in the interest of richer nations to ensure that any vaccines eventually produced to protect against the new coronavirus were shared globally.

"Vaccine nationalism is not good, it will not help us," said the UN health agency's chief Tedros Adhanom Ghebreyesus during the Aspen Security Forum in the United States, via video-link from the WHO's headquarters in Geneva.

"For the world to recover faster, it has to recover together, because it's a globalised world: the economies are intertwined. Part of the world or a few countries cannot be a safe haven and recover."