While so far they had been deployed only there, they might also be sent to other parts of the front line, he said: “There are also already noticeable losses in this category.”
Washington and Seoul have accused Pyongyang of sending more than 10,000 soldiers to help Moscow, after Russia and North Korea signed a landmark defence pact this summer.
The two US foes have strengthened their military ties since Moscow’s invasion of Ukraine in February 2022.
Zelenskyy said last month that 11,000 North Korean troops were in Russia’s western Kursk region and had already suffered losses.
Taken by surprise by the Kursk incursion, Russia has since steadily clawed back territory, halting Ukraine’s advance and rushing reinforcements to the region.
A Ukrainian army source said last month that Kyiv still controlled 800sq km of the Kursk region, down from previous claims it controlled almost 1400sq km.
On Saturday, Russian officials said firefighters were battling a blaze caused by a drone attack in the western Oryol region.
Ukraine has been targeting fuel depots in Russia in retaliation for Moscow’s strikes wreaking havoc on its power-generation network.
The Ukrainian military said on Saturday morning that its forces had attacked a major oil depot in Stalnoi Kon, about 165km into Russian territory.
One of the largest terminals in Russia, it served as the country’s “military industrial complex” supplying the army, the General Staff said.
The governor of Oryol region, Andrei Klychkov, said on Telegram that a fire was blazing at “a fuel infrastructure facility” in Stalnoi Kon after a “massive drone attack”.
By Saturday evening, he said, firefighters appeared to be getting it under control, but residents were advised to keep windows closed and not go out.
Russia’s Interfax news agency reported the attack targeted a facility owned by Transneft-Druzhba, which operates the Druzhba oil pipeline, a key supply route for Russian oil heading to much of central Europe.
Russian media showed images, purportedly of the attack, with clouds of smoke from a fire billowing into the night sky.
Governor Klychkov said there were no casualties in the attack, during which air defences had downed 11 drones.
In Russia’s Belgorod region, which also borders Ukraine, a drone attack killed a 9-year-old boy and wounded his mother and baby sister, Governor Vyacheslav Gladkov said.
He posted photos of the family’s home with a huge hole in the facade and the roof partially torn off.
Ukraine regularly attacks military and energy infrastructure in Russia, sometimes deep into its neighbour’s territory, in response to Russian attacks on its infrastructure.
Kyiv’s General Staff said Russia had attacked overnight with 132 drones, claiming 130 of them were downed or failed to reach targets.
Russia’s military said on Saturday that it had meanwhile downed 60 drones overnight.
– Agence France-Presse
