An unusual public spat between two top Chinese diplomats points to an internal split in Beijing over how to handle rising tensions with a combative U.S. president.

The differences spilled into public view Monday after China's ambassador to the U.S. reaffirmed his opposition to promoting theories that the virus that causes COVID-19 originated in an American military lab. Ambassador Cui Tiankai said in an interview with "Axios on HBO" that he stood by his Feb. 9 statement that it would be "crazy" to spread such theories, even though a foreign ministry spokesman has repeatedly floated the idea on Twitter in recent weeks.

"Such speculation will help nobody. It's very harmful," Cui told Axios. "Eventually, we must have an answer to where the virus originally came from. But this is the job for the scientists to do, not for diplomats."