North Korean troops have not been seen on the frontlines in Russia’s Kursk region for several weeks, a Ukrainian military official said Friday, amid reports of mass casualties among Pyongyang’s forces.

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.

Ukrainian president highlights incursion into Kursk region, alleged Russian losses, London's continued support in talks with UK foreign secretary - Anadolu Ajansı

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engaged in combat since mid-January, South Korea's spy agency told AFP on Tuesday, after Ukraine claimed they had been withdrawn following heavy losses.

The commander described the North Korean troops as "cannon fodder" and said their behavior in combat was erratic.

January, there have been no signs showing North Korean troops deployed to the Russian Kursk region engaging in battle," South Korea's National Intelligence Service (NIS) said, suggesting that heavy losses may have been one of the reasons for their withdrawal.

North Korea sent its best troops to aid Russia in its war against Ukraine. But after months of suffering severe losses, they have been taken off the front line.

Thousands of North Korean troops helped Russia regain some of its territory in the Kursk region following Ukraine's counterattack, but the Russian army is now using them less on the front line and have pulled some back.

South Korea's spy agency says that North Korean forces have suffered more than 3,000 casualties while fighting alongside Russian troops.