Speaking at the World Health Organization's annual summit for member states in Geneva on Tuesday, representatives from the US and several other countries emphasized the importance of identifying how Covid-19 began spreading.

"We underscore the importance of a robust comprehensive and expert-led inquiry into the origins of Covid-19, which is central to ensuring that we are prepared to mitigate and successfully respond to future outbreaks and prevent future pandemics," US representative Jeremy Konyndyk told the World Health Assembly, urging an "expert-led, science-based and independent analysis of origin."

The United Kingdom, the European Union, Australia and Japan were among other nations to call for more progress on the WHO probe.

A team of international experts sent in January to Wuhan, the original epicentre of the Covid-19 outbreak, reported that the virus was likely transferred to humans from bats via an intermediate animal.

They also argued that a theory involving the virus leaking from a laboratory was "extremely unlikely," citing a lack of infected lab workers before the first cases of Covid-19 were reported in December 2019.