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WASHINGTON — New intelligence has prompted the Energy Department to conclude that an accidental laboratory leak in China most likely caused the coronavirus pandemic, though U.S. spy agencies remain divided over the origins of the virus, American officials said on Sunday.

The conclusion was a change from the department’s earlier position that it was undecided on how the virus emerged.

Some officials briefed on the intelligence said that it was relatively weak and that the Energy Department’s conclusion was made with “low confidence,” suggesting its level of certainty was not high. While the department shared the information with other agencies, none of them changed their conclusions, officials said.

Officials would not disclose what the intelligence was. But many of the Energy Department’s insights come from its network of national laboratories, some of which conduct biological research, rather than more traditional forms of intelligence like spy networks or communications intercepts.

Intelligence officials believe the scrutiny of the pandemic’s beginnings could be important to improving global response to future health crises, though they caution that finding an answer about the source of the virus may be difficult or even impossible given Chinese opposition to further research. Scientists say there is a responsibility to explain how a pandemic that has killed almost seven million people started, and learning more about its origins could help researchers understand what poses the biggest threats of future outbreaks.

The new intelligence and the shift in the department’s view was first reported by The Wall Street Journal on Sunday.

Jake Sullivan, the national security adviser, declined to confirm the intelligence. But he said President Biden had ordered that the national labs be brought into the effort to determine the origins of the outbreak so that the government was using “every tool” it had.

In addition to the Energy Department, the F.B.I. has also concluded, with moderate confidence, that the virus first emerged accidentally from the Wuhan Institute of Virology, a Chinese lab that worked on coronaviruses. Four other intelligence agencies and the National Intelligence Council have concluded, with low confidence, that the virus most likely emerged through natural transmission, the director of national intelligence’s office announced in October 2021.

Mr. Sullivan said those divisions remain.

“There is a variety of views in the intelligence community,” he said on CNN’s “State of the Union” on Sunday. “Some elements of the intelligence community have reached conclusions on one side, some on the other. A number of them have said they just don’t have enough information to be sure.”

Mr. Sullivan said if more information was learned, the administration would report it to Congress and the public. “But right now, there is not a definitive answer that has emerged from the intelligence community on this question,” he said.

Some scientists believe that the current evidence, including virus genes, points to a large food and live animal market in Wuhan as the most likely place the coronavirus emerged.

Leaders of the intelligence community are set to brief Congress on March 8 and 9 as part of annual hearings on global threats. Avril D. Haines, the director of national intelligence, and other senior officials would most likely be asked about the continuing inquiry into the virus’s origins.

How the pandemic began has become a divisive line of intelligence reporting, and recent congressional reports have not been bipartisan.

Many Democrats have not been persuaded by the lab leak hypothesis, with some saying they believe the natural causes explanation and others saying they are not certain that enough intelligence will emerge to draw a conclusion.

But many Republicans on Capitol Hill have said they believe the virus could have come from one of China’s research labs in Wuhan. A congressional subcommittee, created when Republicans took over the House in January, has made examining the lab leak theory a central focus of its work. It is expected to convene the first of a series of hearings in March.

“Evidence has been piling up for over a year in favor of the lab leak hypothesis,” said Representative Mike Gallagher, a Wisconsin Republican who sits on the House Intelligence Committee and leads a new House committee on China. “I am glad some of our agencies are starting to listen to common sense and change their assessment.”

On Tuesday, Mr. Gallagher will hold the new committee’s first hearing, looking at the threat the Chinese Communist Party poses to the United States. Future hearings, Mr. Gallagher said, will look at biosecurity and China’s efforts to influence international organizations like the World Health Organization.

“Where our committee can have a role is teasing out what this communicates about the DNA of the Chinese Communist Party, an organization that was willing to cover up the origins of the pandemic and thereby cost us critical days, months and weeks and millions of lives in the process,” Mr. Gallagher said in an interview on Sunday.

Chinese officials have repeatedly called the lab leak hypothesis a lie that has no basis in science and is politically motivated.

Early in the Biden administration, the president ordered the intelligence agencies to investigate the pandemic’s origins, after criticism of a W.H.O. report on the matter. While there was material that had not been thoroughly examined by intelligence officials, the review ultimately did not yield any new consensus inside the agencies.

The March 2021 report by the W.H.O. said it was “extremely unlikely” that the virus emerged accidentally from a lab. But China appointed half the scientists who wrote the report and exerted major control over it. American officials have been largely dismissive of that work.

The intelligence agencies have said they do not believe there is any evidence that the coronavirus that causes Covid-19 was created deliberately as a biological weapon. But they have said that whether it emerged naturally, perhaps from a market in Wuhan, or escaped accidentally from a lab is the subject of legitimate debate.

Anthony Ruggiero, a scholar at the Foundation for Defense of Democracies and a former National Security Council staff member focusing on biodefense issues during the Trump administration, said he believed China is still “hiding crucial information” about how the virus emerged. He said the lab leak theory should not be dismissed.

“The lab leak origin for the Covid-19 pandemic is not, and was not, a conspiracy theory,” he said.

Benjamin Mueller and Sheryl Gay Stolberg contributed reporting.