President Biden ordered U.S. intelligence agencies on Wednesday to investigate the origins of the coronavirus, indicating publicly that his administration takes seriously the possibility that the virus was accidentally leaked from a lab, as well as the prevailing theory that it was transmitted by an animal to humans.
In a statement, Mr. Biden made it clear that the intelligence agencies had not reached consensus on how the virus, which sparked a pandemic and has killed almost 600,000 people in the United States, originated. But he directed them to “redouble their efforts” and report back to him in 90 days.
Mr. Biden’s statement, his most public and expansive yet on the uncertainty around how the virus spread to humans, came as top health officials renewed their appeals this week for a more rigorous investigation and an earlier report by an international team of experts faced mounting criticism for dismissing the possibility that it had accidentally escaped from a Chinese laboratory.
Just in the past several days, the White House had downplayed the need for an investigation led by the United States and insisted that the World Health Organization was the proper place for an international inquiry. Mr. Biden’s statement on Wednesday was an abrupt shift, though officials declined to be specific about what had changed.
“What has changed is, he wants to give another 90 days to dig a little deeper, to double down — the I.C. to double down their efforts,” Karine Jean-Pierre, the deputy White House press secretary, said referring to the intelligence community. “The W.H.O. doing their thing and the I.C., doing what they’re doing currently is not mutually exclusive.”
But Mr. Biden’s comments suggested that his own government’s review of the evidence made it that much more urgent for American investigators to take the lead. In his statement, Mr. Biden said that he had asked his national security adviser in March to task intelligence officials with a report on their latest analysis of the virus’s origins, which he said he received earlier this month before asking for “additional follow-up.” He said the intelligence community had “coalesced around two likely scenarios” but not definitively answered the question.
“Here is their current position: ‘while two elements in the IC leans toward the former scenario and one leans more toward the latter — each with low or moderate confidence — the majority of elements do not believe there is sufficient information to assess one to be more likely than the other,’” Mr. Biden said.
The calls from Mr. Biden and other top American health officials were the latest in a series of White House demands in recent months that any such inquiry be free from Chinese interference. But they drew additional attention as some scientists have expressed a new openness to the idea of a lab accident and the W.H.O. grappled with how to respond.
A joint W.H.O.-China inquiry whose findings were released in March dismissed as “extremely unlikely” the possibility that the virus had emerged accidentally from a laboratory.
Suggestions that the coronavirus may have been accidentally carried out of a laboratory in late 2019 in the Chinese city of Wuhan were largely drowned out last year by scientists’ accounts of its likely path from an animal host to humans in a natural setting.
Many scientists, including those who lead American health agencies, believe that a so-called spillover event remains the most plausible explanation for the pandemic. But the joint inquiry by the W.H.O. and China did not settle the matter: The Chinese government repeatedly tried to bend the investigation to its advantage, and Chinese scientists supplied all the research data used in the final report.
Dr. Francis Collins, the National Institutes of Health director, criticized the report while testifying to Senate lawmakers Wednesday on the agency’s budget.
“It is most likely that this is a virus that arose naturally. But we cannot exclude the possibility of some kind of a lab accident. That’s why we’ve advocated very strongly that W.H.O. needs to go back and try again after the first phase of their investigation really satisfied nobody,” Dr. Collins said. “And this time we need a really expert driven, no-holds-barred collection of information, which is how we’re mostly really going to find out what happened.”
Echoing his past comments, Dr. Anthony S. Fauci, the nation’s top expert on infectious diseases, agreed the virus was “most likely” naturally occurring. “But no one knows that 100 percent for sure,” he said at the same hearing. “And since there’s a lot of concern, a lot of speculation, and since no one absolutely knows that, I believe we do need the kind of investigation where there’s open transparency.”
In early March, a small group of scientists calling themselves the Paris group released an open letter calling for an inquiry separate from the team of independent experts sent to China as part of the W.H.O. investigation.
This month, a group of 18 scientists said in a letter published in the journal Science that there was not enough evidence to decide whether a natural origin or an accidental laboratory leak caused the Covid-19 pandemic.
After the findings of the joint inquiry by China and the W.H.O. were released in March, the director of the W.H.O., Dr. Tedros Adhanom Ghebreyesus, said that the lab leak theory required further study, adding that he did not believe that “this assessment was extensive enough.”
And countries including Australia, Germany and Japan have continued at this week’s W.H.O. meeting to call for firmer steps toward a more comprehensive investigation.