US President Donald Trump warned on Saturday that China could face consequences if it was "knowingly responsible" for the coronavirus pandemic.
"It could have been stopped in China before it started and it wasn't," Mr Trump told reporters at a White House briefing.
"And now the whole world is suffering because of it."
Mr Trump was asked whether China should suffer consequences for the pandemic which began in the central city of Wuhan in December and has killed more than 157,000 people around the world.
"If they were knowingly responsible, certainly," he said. "If it was a mistake, a mistake is a mistake.
"But if they were knowingly responsible, yeah, then there should be consequences," Mr Trump said.
"Was it a mistake that got out of control or was it done deliberately?" he said. "That's a big difference between those two.
"In either event, they should have let us go in," he said, referring to a US offer of scientific assistance.
"We asked to go in early. And they didn't want us in. I think they knew it was something bad and they were embarrassed."
"They said they're doing an investigation," the president said. "So let's see what happens with their investigation. But we're doing investigations also."
The Trump administration has said it does not rule out that the coronavirus was spread accidentally from a laboratory researching bats in Wuhan.
Chinese Foreign Ministry spokesman Zhao Lijian – who has alleged that the US military may have taken the virus into China – rejected US media reports on the subject and said there was "no scientific basis" for the assertion that China let the virus spread.
Mr Trump also cast doubt on official Chinese figures which showed the country had suffered 0.33 deaths per 100,000 people.
"The number's impossible," he said. "It's an impossible number to hit."
The United States, according to a chart displayed at the briefing, has had 11.24 deaths per 100,000 people, while France has had 27.92 and Spain 42.81.