The World Health Organization-China report blaming the origins of the COVID-19 pandemic on animal-to-human transmission comes from a study that was "flawed from the start" and the research must start over, Jamie Metzl, a Clinton-era National Security Council member and part of a WHO advisory committee on genetic engineering, said Tuesday. 

"I have read the full report, and I think we should be very upset about this process," Metzl said on Fox News' "Fox and Friends." "It is entirely inadequate. They have done a thorough job of investigating the first hypothesis that you mentioned that it jumped from bats to other animals to humans and that's possible. They entirely discounted without any significant inquiry the very likely possibility that COVID-19 began from an accidental lab leak."

The report isn't from the WHO alone, but is a joint report of a study between an independent advisory committee the organization appointed and its counterparts from the Chinese government, Metzl continued. 

"The Chinese government was never going to sign off" on the possibility that the deadly virus escaped from the Wuhan Institute of Virology, located in the city where the first outbreak occurred, Metzl added. 

Metzl, along with two dozen experts including virologists, signed an open letter earlier this month that calls for a new international inquiry to return to China, reports CBS News.  

In the letter, the experts say the WHO team was not allowed the independence or the access needed to "carry out a full and unrestricted investigation" focused on a possible accidental leak from the Wuhan laboratory. 

In an interview on "60 Minutes" Sunday, Metzl pointed out that the Wuhan facility is a Chinese level four virology institute and contains the world's largest collection of bat viruses, including bat coronaviruses.

But with the team focusing mainly on the hypothesis that the virus started with animals, that lets the Chinese government "off the hook," Metzel said Monday. "From day one, they have been destroying samples, hiding records, and imprisoning journalists. They have a universal gag on scientists. That's why any process that relies on the goodwill of the Chinese government is flawed from the start."

Metzl, meanwhile, said he agrees with comments from Dr. Anthony Fauci, the head of the National Institute of Allergy and Infectious Diseases, who said over the weekend that it is "entirely conceivable" that the coronavirus had been spreading for weeks before it was recognized at the end of December, which gave it time to adapt to a human. 

"That would really be completely consistent with just jumping species in the wild," said Fauci in the clip. "The other theory that people have is that somehow it did that in a lab and it accidentally escaped. I think the most likely one that, in nature, in the wild, it adapted itself."

"I have a lot of respect for Dr. Fauci and I think he is right," said Metzl. "It is conceptually possible that this happened in the wild. The evidence for it so far is nonexistent, but we know that past outbreaks have happened that way. He also recognizes that a lab leak is very, very possible. Dr. (Robert) Redfield made a stronger statement over the weekend and I think we need to be thoroughly examining both of these hypotheses." 

But no matter what the final determination is, it's important to find out how the pandemic began, Metzl said. 

"When a plane crashes, we don't say let's just redouble our efforts for airline safety," he said. "We say let's figure out why this particular plane crashed because we know there are other planes in the air. We need to know how this terrible pandemic started because that needs to be our priority in fixing our biggest problems. Until we do that we are unnecessarily adding risk."

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