We still don’t know for sure if there are North Korean troops fighting in Russia against Ukrainian forces. Perhaps we never will. But Ukraine’s case for their presence was not made stronger by the sudden announcement on January 30 that they were gone.

North Korean soldiers previously fighting alongside Russia's army on the Kursk front line appear not to have been engaged in combat since mid-January, South Korea's spy agency told AFP on Tuesday, after Ukraine claimed they had been withdrawn following heavy losses.

Ukrainian special operations forces have given an insight into the brutal, near-suicidal tactics of the North Koreans they have faced in intense fighting in the Russian border region of Kursk.