Washington, May 24 : US' top infectious disease expert Anthony Fauci has said he is "not convinced" Covid-19 developed naturally, and has called for an open investigation into China to unravel the virus' origins, the media reported. Fauci was asked during a Poynter event, "United Facts of America: A Festival of Fact-Checking", earlier this month, about whether he was confident that Covid developed naturally. "No actually. I am not convinced about that, I think we should continue to investigate what went on in China until we continue to find out to the best of our ability what happened," Fauci, director of the National Institute of Allergies and Infectious Diseases (NIAID) was quoted as saying, Fox News reported on Sunday. "Certainly, the people who investigated it say it likely was the emergence from an animal reservoir that then infected individuals, but it could have been something else, and we need to find that out. So, you know, that's the reason why I said I'm perfectly in favor of any investigation that looks into the origin of the virus," Fauci added. The Coronavirus was first reported from the Chinese city of Wuhan in December 2019. Reports have claimed of the virus' origin from a lab there. Further, Fauci called for an investigation into China during a Senate hearing last week, the New York Post reported. aceDo you think it's possible that Covid-19 arose from a lab accident a in Wuhan, and should it be fully investigated?" Senator Roger Marshall (R-Kansas), a doctor, asked Fauci during a Senate hearing on May 11. "That possibility certainly exists, and I am totally in favour of a full investigation of whether that could have happened," Fauci replied. Another Senator had claimed that funding through the National Institutes of Health (NIH) had been funneled to the controversial Wuhan Institute of Virology -- the Chinese lab that is believed to have played a role in the initial outbreak of Covid-19, the Fox News reported. Rand Paul specifically zeroed in on gain of function research -- which works on making pathogens deadlier or more easily transmissible. He alleged that a US virologist had been working with the Chinese institute on such research and said it was funded by the NIH. "I do not have any accounting of what the Chinese may have done, and I'm fully in favour of any further investigation of what went on in China," Fauci said. "However, I will repeat again, the NIH and NIAID categorically have not funded the gain of function research to be conducted in the Wuhan Institute of Virology," he added Fauci, who is also a top adviser to President Biden on the coronavirus pandemic, had in the initial months of the pandemic last year dismissed the theory that Covid originated from China. He stated that the virus most likely "evolved in nature and then jumped species", as opposed to being "artificially or deliberately manipulated". While the Trump administration officials have long argued there is a high chance Covid-19 was the result of a lab leak, the World Health Organization declared, last week, that the lab leak theory "extremely unlikely". However, WHO chief Tedros Adhanom Ghebreyesus said the research team's assessment on whether the virus entered the human population following a laboratory incident was not "extensive enough" and requires further investigation. White House press secretary Jen Psaki said, this week, the Biden administration has conveyed both publicly and privately that the Chinese government was "not transparent from the beginning", the report said. /IANS