Anonymous Ukrainian and US officials have told The NY Times that North Korean soldiers fighting for Russia have been pulled from the front lines in Kursk region, where Ukraine has waged a cross-border ground offensive since last August, after suffering heavy losses.
It was widely reported that some 11,000 North Koreans were sent by Kim John Un to assist the Russian army. So far, reports suggest the foreign troops have only been deployed in southern Russian territory which is partially occupied by Ukraine forces.
"Ukrainian troops who have fought against the North Koreans have described them as fierce warriors. But disorganization in their ranks and a lack of cohesion with Russian units have quickly driven up casualties, a Ukrainian official said," the officials claimed to the Times.
"Since arriving on the battlefield, the North Korean soldiers have been left to fend for themselves, advancing with few armored vehicles and rarely pausing to regroup or fall back, according to Ukrainian officials and frontline troops," the report says.
None of this can be independently verified, and in the past Western and Ukrainian officials have used such anonymous quotes to the Times to advance wartime propaganda; however, there have been some indicators of disorganization and lack of communication and experience among the North Korean and Russian troops as they struggle to coordinate on the battlefield.
Pyongyang also chiefly sent foot soldiers in, and not entire support units for example with armor or heavier weapons. This does indeed make these DPRK forces more vulnerable and entirely reliant on their Russian allies. This also leaves them more exposed to land mines and small drone attack.
But North Korea has indicated it's sent its "best-trained special operations troops" to help Putin's forces, and additional reinforcements are expected "within the next two months," the NYT reported last week.
The Times further frames the NK troops being pulled back in the following context:
The longer Ukrainians troops hold Kursk, the more embarrassing it becomes for Russia’s president, Vladimir V. Putin. Though Mr. Putin has vowed to expel the Ukrainian forces, he has been hesitant to divert troops from the main Russian operations in eastern Ukraine, in part to similarly strengthen his hand in future negotiations.
...Many of the soldiers are among North Korea’s best-trained special operations troops, but the Russians appear to have used them as foot soldiers, sending them forth in waves across fields studded with land mines to be mowed down by heavy Ukrainian fire.
It should be added that morale among these foreign forces must be low if they generally come to be perceived as 'expendable'. This is a narrative Kiev has advanced, at least.