The US intelligence community has determined Covid-19 "was not manmade or genetically modified", though it is still investigating the virus' origins.
The National Intelligence chief's office said agencies are looking into whether the outbreak began from animal contact or a laboratory accident.
President Donald Trump later suggested he had seen evidence the virus came out of a Chinese laboratory.
China has rejected the theory and criticised the US response to Covid-19.
What did the intelligence chief say?
The Office of the Director of National Intelligence, which oversees US spy agencies, said on Thursday it concurs with the "wide scientific consensus" regarding Covid-19's natural origins.
"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 virus was first detected in Wuhan, China. There are now over 3.2 million cases worldwide and more than 231,000 deaths.
Thursday's statement is the first clear response from US agencies debunking conspiracy theories – both from the US and China – about the virus as a purported bioweapon.
The idea that the coronavirus could have inadvertently leaked from a laboratory has not yet been disproven.
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What did President Trump say?
Taking questions at the White House on Thursday, Mr Trump stoked this theory.
He was asked by a reporter: "Have you seen anything at this point that gives you a high degree of confidence that the Wuhan Institute of Virology was the origin of this virus?"
The president replied: "Yes, I have. Yes, I have. And I think the World Health Organization should be ashamed of themselves because they're like the public relations agency for China."
He added: "Whether they [China] made a mistake, or whether it started off as a mistake and then they made another one, or did somebody do something on purpose?
"I don't understand how traffic, how people weren't allowed into the rest of China, but they were allowed into the rest of the world. That's a bad, that's a hard question for them to answer."
The New York Times reported on Thursday that senior White House officials have asked the US intelligence community to investigate whether the virus came from a Wuhan research laboratory.
Intelligence agencies have also been tasked with determining if China and the WHO withheld information about the virus early on, unnamed officials told NBC News on Wednesday.
What's the background?
Mr Trump has recently been escalating his rhetoric with China over the pandemic after what officials within the US president's administration had described as a truce with Beijing on the war of words.
Mr Trump has often blamed China at briefings, accusing its officials of covering up the virus early on and saying they could have stopped the disease from spreading.
He has similarly criticised the WHO and withdrew US funding for the global body.
China's Foreign Ministry, meanwhile, has accused the Trump administration of trying to distract from its own pRead More – Source