The World Health Organization reiterated on Friday that the new coronavirus was of natural origin after US President Donald Trump claimed he had seen evidence it originated in a Chinese lab, AFP reports.

Scientists believe the killer virus jumped from animals to humans, emerging in China late last year, possibly from a market in Wuhan selling exotic animals for meat.

Trump claimed Thursday that he had seen proof that the Wuhan Institute of Virology was actually the source of the outbreak, although he refused to give details.

Asked about Trump's claim during a virtual press conference, WHO emergencies chief Michael Ryan stressed that the UN health agency had “listened again and again to numerous scientists who have looked at the sequences” of the virus.

“We are assured that this virus is natural in origin,” he said, reiterating a stance the UN agency has expressed previously.