Tokyo urged Beijing to stop taking nCoV anal samples after many Japanese citizens suffered "severe psychological pain".

"Some Japanese citizens have called the embassy in China, saying they have suffered severe psychological pain from taking samples for anal testing," said Japan Chief Cabinet Office Katsunobu Kato.

Mr. Kato added that Tokyo has not received any answer from Beijing about changing the sampling procedure, affirming Japan will continue to call on China to choose an alternative.

China says that taking nCoV anal samples from the anus may be more effective than conventional oropharyngeal drainage, since the virus can last longer in the digestive system.

Chinese state media reported that when the anal nCoV method was used in Beijing during a small outbreak in January, it caused controversy on Weibo, with many saying the method "terrifying"

However, Beijing officials also admit it is difficult to apply the anal nCoV test as widely as other methods, which are used to test millions of people, because it is "inconvenient" for both

State Department spokesman Ned Price said on February 25 that some members of the US delegation were also subject to this sampling method and had expressed objections.