A Chinese virologist, who was among the first to suggest the COVID-19 virus leaked from a Wuhan lab, said that US top coronavirus advisor Anthony Fauci's emails prove that she was right all along.

A trove of Fauci's emails covering the onset of the coronavirus outbreak was released this week to media under a freedom of information request.

In one email sent last April, an executive at a health charity thanked Fauci for publicly stating that scientific evidence does not support the lab-leak theory.

Dr. Li-Meng Yan was one of the first to research the emerging coronavirus and previously revealed she was forced into hiding after accusing Beijing of a cover-up, New York Post reported.

Now, as international leaders finally focus on her Wuhan lab-leak theory, the scientist told Newsmax that Fauci's emails contain "a lot of useful information" suggesting he always knew more than he revealed.

"They verify my work from the very beginning, even from last January, that these people know what happened, but they choose to hide for the Chinese Communist Party and for their own benefits," Yan insisted speaking of the treasure trove of documents released this week.

"He knows all these things," she insisted of Fauci and the apparent gain-of-function work carried out by the now-notorious Wuhan Institute of Virology in the heart of the city where the pandemic first emerged.

One email, she said, showed that "Dr. Fauci even back to 1st of February last year immediately realized that there would be gain-of-function experiment involved in the COVID-19 virus."

Over 3,000 pages of emails were obtained by the Washington Post, Buzzfeed News and CNN through Freedom of Information Act (FOIA) requests, date from January to June 2020.

The emails have sparked the debate whether Fauci chose to remain mum despite knowing about the onset of the virus.

The emails revealed about early days of the US Covid outbreak. Dr Fauci and his colleagues took notice, in the early days, of the theory that COVID-19 may have leaked from a laboratory in Wuhan, China.

In an interview with CNN, Fauci said the email had been taken out of context by critics and he had an "open mind" about the origin of the virus.

With regard to the "lab leak" email, the doctor told CNN that he still finds it unlikely that a Wuhan laboratory released the virus.

"I don't remember what's in that redacted [email], but the idea I think is quite far-fetched that the Chinese deliberately engineered something so that they could kill themselves as well as other people," he said.

Amid criticism of an inconclusive international probe into the virus' origins and new reports of Covid-related illness in the region weeks before it was officially identified, the theory is once again sparking debate.