Ukraine’s military intelligence chief denied recent media reports that North Korean troops deployed to Russia have temporarily retreated from the front lines, in an interview published on Wednesday.

North Korean troops, largely special ops forces, have suffered high casualties in bloody assaults not unlike other units, including prison units.

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engaged in combat since mid-January, South Korea's spy agency told AFP on Tuesday, after Ukraine claimed they had been withdrawn following heavy losses.