United States President Donald Trump claims he has seen evidence the novel coronavirus originated in a Wuhan laboratory and threatened to slap new tariffs on the Asian economic power.

Speaking at a White House news conference, the US president said China either could not stop spread of the virus, or let it spread.

Mr Trump said he feels confident the virus came from the Wuhan Institute of Virology, adding that US authorities were “looking at it very, very strongly”.

“We’re going to see where it is – we’re going to see where it comes from,” he said, “There’s a lot of theories.”

“China might even tell us,” he added.

Asked by a reporter whether he had seen “anything that gives you a high degree of confidence” the institute was the origin of the virus, he responded: “Yes I have.”

And asked a few minutes later what gave him such confidence, he said: “I can’t tell you that. I’m not allowed to tell you that.”

He declined to say whether he holds Chinese President Xi Jinping responsible for what he feels is misinformation.

But he did criticise China for failing to contain the virus, saying: “This is something that could have been contained at the original location and it could have been contained relatively easily.”

He later added: “One of two things happened. They either couldn’t do it from a competence standpoint or they let it spread.

“I would say probably it got out of control.”