His executive order targeted the elimination of what is called gain-of-function, which studies how viruses become more powerful. The United States funded that sort of research at the Wuhan lab, in the city where the initial outbreak was reported. But a competing theory is that a person somehow came into contact with an infected animal.

US President Donald Trump has signed an executive order banning US-funded virus research amid arguments between America and China about the origin of Covid.

The Chinese accusations come after the White House revamped its COVID-19 information earlier this month to push out the assertion that COVID-19 leaked out of a lab in the Wuhan Institute of