The source of the virus is a mystery. The broad scientific consensus is that the novel coronavirus originated in bats.
Fox News reported on Wednesday that the virus originated in a Wuhan laboratory as part of China's effort to demonstrate the capability of its efforts in identifying and combating viruses. Trump has said his government is seeking to determine whether the virus emanated from a laboratory in China.
"A lot of strange things are happening but there is a lot of investigation going on. And we're going to find out," Trump told reporters at the White House.
Trump also cast doubt on China's death toll, which was revised up on Friday. China said 1,300 people who died of the coronavirus in the Chinese city of Wuhan - half the total - were not counted, but dismissed allegations of a cover-up.
The US president said on Friday that many more people must have died in China than in the United States, which is currently the epicenter of the global pandemic and has reported the largest number of deaths in the world linked to the virus.
"We don't have the most in the world deaths. The most in the world has to be China. It's a massive country. It's gone through a tremendous problem with this, a tremendous problem - they must have the most," Trump told reporters.
China reported that 4,632 people have died of the novel coronavirus within its borders. US coronavirus deaths topped 35,400 on Friday, according to a Reuters tally.Washington and Beijing have publicly sparred over the virus repeatedly. Trump initially praised China's response to the outbreak, but he and his top aides have also referred to it as the "Chinese virus.