North Korea sent troops to clear mines in Russia’s Kursk region earlier this year, leader Kim Jong-un said in a speech carried on Saturday by state media, a rare acknowledgement by Pyongyang of the deadly tasks assigned to its deployed soldiers.

According to South Korean and western intelligence agencies, North Korea has sent thousands of troops to support Russia’s nearly four-year invasion of Ukraine.

Analysts say Russia is giving North Korea financial aid, military technology, food and energy supplies in return, allowing the diplomatically isolated nation to sidestep tough international sanctions on its nuclear and missile programmes.