The US intelligence community has concluded that the novel coronavirus gripping the globe originated in China but was not man-made or engineered.
"The entire Intelligence Community has been consistently providing critical support to US policymakers and those responding to the Covid-19 virus, which originated in China," the Office of the Director of National Intelligence said in a statement.
"The Intelligence Community also concurs with the wide scientific consensus that the Covid-19 virus was not man-made or genetically modified.
"The [Intelligence Community] will continue to rigorously examine emerging information and intelligence to determine whether the outbreak began through contact with infected animals or if it was the result of an accident at a laboratory in Wuhan."
The statement came after US President Donald Trump suggested on Monday that he might seek damages from China over the outbreak.
News reports say Trump has tasked US spies to find out more about the origins of the virus, at first blamed on a Wuhan, China wet market selling exotic animals like bats, but now thought possibly to be from a virus research laboratory nearby.
Suggesting that Beijing has not been forthcoming about the disease, which has infected about 3.2 million people and killed more than 227,000, Trump said Monday that there were many options to "hold them accountable".
"We are not happy with China," he said.
"We are not happy with that whole situation because we believe it could have been stopped at the source."
The US intelligence directorate said it always boosts resources for study and analysis during national security crises.
The Intelligence Community "will continue to rigorously examine emerging information and intelligence to determine whether the outbreak began through contact with infected animals or if it was the result of an accident at a laboratory in Wuhan", it said.
The theory that the virus was man-made has circulated since the epidemic erupted in China in December and January. It was largely touted by anti-China activists who suggested that the coronavirus had been developed by Chinese scientists in a government biological weapons laboratory from which it then escaped.
Trump addressed the theory earlier this month, saying: "More and more, we're hearing the story."
In a survey released April 8, the Pew Research Centre said 29 per cent of Americans believed the virus was created in a laboratory, either purposely (23 per cent) or by accident (6 per cent).
No evidence has been offered to support the theory, and scientists say there is no indication in the virus' genetic makeup that it was manipulated in a laboratory.
Scientists say the virus arose naturally in bats. Even so, Secretary of State Mike Pompeo and others have pointed fingers at an institute that is run by the Chinese Academy of Sciences. It has done groundbreaking research tracing the likely origins of the Sars virus, finding new bat viruses and discovering how they could transfer to people.
"We know that there is the Wuhan Institute of Virology just a handful of miles away from where the wet market was," Pompeo said two weeks ago.
The institute has an address 13km from the market that is considered a possible source.
US officials say the American Embassy in Beijing flagged concerns about potential safety issues at the lab in Wuhan in 2018, but they have yet to find any evidence the virus originated there nearly two years later.
The Chinese government said on Thursday that any claims that the coronavirus was released from a laboratory are "unfounded and purely fabricated out of nothing".
Foreign Ministry spokesman Geng Shuang cited the institute's director, Yuan Zhiming, as saying the lab strictly implements biosecurity procedures that would prevent the release of any pathogen.
"I would like to point out again that the origin of the virus is a complex scientific issue, and it should be studied by scientists and professionals," Geng said.
Geng also criticised US politicians who have suggested China should be held accountable for the global pandemic, saying they should spend their time on "better controlling the epidemic situation at home".
But a Chinese government spokesman, Zhao Lijian, demonstrated that China was not above sowing confusion in the face of the pandemic. He tweeted in March the falsehood that the virus might have come from the US Army.