Donald Trump said he had seen strong evidence that Covid-19 originated from a scientific laboratory in Wuhan, in an escalation of his attacks on China over its role in the spread of coronavirus.
Asked on Thursday if he had seen information that gave him a “high degree of confidence” that the virus emanated from the Wuhan Institute of Virology in China, Mr Trump told reporters: “Yes, I have.”
When pressed on what had given him the confidence to make the claim, the US president said: “I’m not allowed to tell you that.”
At the same event, however, Mr Trump said his administration was still investigating the origins of the virus, in comments that partly undermined his confidence in the evidence that he had been shown.
“We’re looking at exactly where it came from, who it came from, how it happened,” said Mr Trump, adding that the results should come soon.
Scientists studying Covid-19 think it was likely to have spread from bats to humans via a host animal. They have not ruled out an accidental lab spillage but think it unlikely. China has denied that it came from the lab.
Mr Trump was also asked about a Washington Post report that he was considering cancelling US debt held by China as punishment for its handling of the virus. He said there were other ways to punish China, and did not view it as a smart approach to tackle the issue because of the effect such a move would have on the US currency.
“When you start playing that game, you’re really hurting the sanctity, the importance of the greatest currency on earth,” he said. “We can do it in other ways. We can do it with tariffs. We can do it other ways even beyond that, without having to play that game. That’s a rough game.”
Mr Trump has blamed China for the spread of Covid-19 as his handling of the crisis has come under scrutiny. He has accused Beijing of holding back information about the outbreak in Wuhan, and entertained several unproven theories about the disease’s origin.
The office of the director of US national intelligence earlier released a statement rejecting some of the conspiracy theories that have gained traction among some extreme rightwing China critics in the US.
“The intelligence community also concurs with the wide scientific consensus that the Covid-19 virus was not man-made or genetically modified,” said the DNI, which is led by Richard Grenell, a Trump loyalist who has been tapped to take the role temporarily.
The statement said the intelligence community had not concluded if the virus came from the Wuhan lab. It said intelligence officials would “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”.
Mike Pompeo, the secretary of state who has described the illness as the “Wuhan virus”, has accused China of destroying virus samples. He also criticised China for failing to grant access to the Wuhan lab, which was studying bat coronaviruses, and floated the possibility of an accidental release from the facility.
The endorsement of unproven theories by Mr Trump has raised concerns that his administration is politicising intelligence to help him blame China, which would play well with his political base as he campaigns for re-election against Joe Biden, the presumptive Democratic party presidential nominee.
Republican hawks have applauded the push by the administration to attack China over its alleged lack of transparency about the disease and unwillingness to co-operate with US government scientists.
In China, where it is a national holiday on Friday, the ministry of foreign affairs declined to comment.
Follow Demetri Sevastopulo on Twitter: @dimi