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.

All North Korean recruits are taught a song that includes a verse about saving their last bullet for themselves to avoid capture, one former soldier told NBC News.

British intelligence has reported that one-third of the troops deployed alongside Russian forces in Ukraine are already out of action. Pyongyang sent a contingent of 12,000 soldiers to Russia to assist local forces in regaining lost territory in the Kursk region,

While Russia has received support from various allies, recent reports suggest a growing presence of North Korean troops on the battlefield. Their involvement raises questions about their role in the conflict and the equipment they bring to the fight.

Troops from North Korea appear to have fallen back from Russia's frontline after suffering heavy losses when engaging Ukrainian forces.