The war in Ukraine is now partly a battle for the attention of the White House. In such circumstances, the capture of Chinese citizens on the battlefield is a boost to Kyiv and Volodymyr Zelensky, Ukraine’s president. Mr Zelensky wasted little time in casting the men as proof that “one more” nation – China – had joined the war against his country.

A Beijing official pushed back on Ukraine’s claim that there were significant numbers of Chinese troops fighting alongside Russian forces. An official said the idea that many Chinese nationals