Anal coronavirus tests involve inserting a cotton swab 3-5cm into the anus and gently rotating it.
They were first used in China in January, as health officials claimed that the tests are more accurate in detecting coronavirus, saying it can survive longer in the anus or in fecal matter versus in other parts of the body.
“Given that the method is not as convenient as throat swabs, it will only be applied to key groups at quarantine centers,” officials were quoted saying in Chinese state media.
On Thursday, China denied forcing the diplomats to have the tests.
“China has never requested US diplomatic personnel in China to undergo anal swabs,” foreign ministry spokesman Zhao Lijian said at a press briefing.