The FBI chief has claimed a lab leak of Covid is the "most likely" origin of the pandemic virus.
Christopher Wray, during an interview on Tuesday, has said for the first time Covid may have originated in a "Chinese government-controlled lab".
He said: "The FBI has for quite some time now assessed that the origins of the pandemic are most likely a potential lab incident in Wuhan.
"Here you are talking about a potential leak from a Chinese government-controlled lab."
However, the White House revealed there is no US consensus on the potential origins of the virus.
The findings came after the FBI's classified judgement, along with The US Department of Energy, was made public.
Mr Wray said the report was concluded after agencies finished their investigation into the origins of the potential disease.
He said: "The FBI has folks, agents, professionals, analysts, virologists, microbiologists, etc, who focus, specifically, on the dangers of biological threats, which includes things like novel viruses like Covid, and the concerns that in the wrong hands some bad guys, some hostile nation state, a terrorist, a criminal, the threats that that could pose."
"So here, you’re talking about a leak at a Chinese government-controlled lab that killed millions of Americans, and that’s precisely what that capability was designed for."
However, since the FBI filed their report, China has tried to undermine their work, he claimed.
Mr Wray claimed the Chinese government allegedly tried to cover-up the FBI's findings in 2021.
The US initially had "moderate confidence" the pandemic was due to an accidental leak at the Wuhan Institute of Virology.
The FBI chief revealed: "I will just make the observation that the Chinese government, it seems to me, has been doing its best to try to thwart and obfuscate the work here, the work that we're doing, the work that our US government and close foreign partners are doing, and that's unfortunate for everybody."
Chinese Foreign Ministry spokeswoman Mao Ning rejected claims they were behind the virus on Monday and claimed it was an attempt to smear the country.
She said in a press conference: "'Certain parties should stop rehashing the "lab leak" narrative, stop smearing China and stop politicising origins-tracing."
She accused Washington of "political manipulation" and claimed "the conclusions they have reached have no credibility to speak of."
Mao said China had worked with agencies including the World Health Organisation in 2021 to look at how the virus spread.
However, they rejected the WHO's request to hold a second part of the investigation.
Mr Wray said China "has been doing its best to try to thwart and obfuscate" efforts to identify the source of the virus.
