Open this photo in gallery

       Workers in protective suits disinfect the compound of a primary school before schools reopen for the upcoming semester, in Wuhan, Hubei province, China, on Aug. 25, 2021.

       CHINA DAILY/Reuters

       U.S. intelligence agencies have not been able to determine if the coronavirus pandemic was the result of an accidental leak from a lab or if it emerged more naturally, according to declassified portions of a report to the White House released Friday.

       The country’s spy agencies, the Office of the Director of National Intelligence said, are unlikely to reach a conclusion without more co-operation from China or a new source of information.

       In a statement, President Joe Biden said the United States would continue working to understand the origins of the virus and he called on China to be more transparent about what led to the virus emerging there in late 2019 before spreading rapidly across the globe.

       “We will do everything we can to trace the roots of this outbreak that has caused so much pain and death around the world, so that we can take every necessary precaution to prevent it from happening again,” Mr. Biden said. “Critical information about the origins of this pandemic exists in the People’s Republic of China, yet from the beginning, government officials in China have worked to prevent international investigators and members of the global public health community from accessing it.”

       As debates about the origins of the pandemic and China’s role intensified, Mr. Biden ordered the country’s intelligence agencies three months ago to draft a report on the source of the virus.

       After the review, the National Intelligence Council and four other intelligence community elements reported that they believe the virus that causes COVID-19 was most likely created by “natural exposure to an infected animal through an animal infected with it, or close progenitor virus.”

       Before the review was conducted only two agencies favoured the natural exposure theory. But the new report said the intelligence council and other agencies favouring the natural theory only had only low confidence in their conclusions – a sign that the intelligence behind the assessment was not strong and that conclusions could change.

       On the other side of the debate, one agency, with moderate confidence, said it had concluded that the pandemic was the result of “a laboratory-associated incident” in China.

       The announcement from the director of national intelligence did not identify the agency that favoured the laboratory-leak theory. But current and former officials said the FBI believed that the virus was created within the lab.

       Our Morning Update and Evening Update newsletters are written by Globe editors, giving you a concise summary of the day’s most important headlines. Sign up today.

       Story continues below advertisement