North Korean troops fighting alongside Russia in its war against Ukraine on the frontline in Kursk have been "withdrawn", according to a Ukrainian military official.
Special Operations Forces spokesman Oleksandr Kindratenko said Ukrainian forces had not "seen or detected any activity or military clashes with the North Koreans" in the past three weeks.
"We believe that they have been withdrawn because of the heavy losses that were inflicted," he said.
The North Korean deployment, that was never officially confirmed by Russian or North Korea, came after Ukraine launched a cross-border offensive in Kursk in August.
It comes almost exactly three weeks after Ukrainian president Volodymyr Zelenskyy claimed two injured North Korean soldiers were captured in the Kursk region and transported to Kyiv.
Mr Zelenskyy said in late December that Ukraine had captured several seriously wounded North Korean soldiers who later died.
Ukrainian officials have said that wounded North Korean troops were blowing themselves up with grenades rather than being taken alive.
North Korean soldiers were first deployed to Russia in October to support Vladimir Putin's invasion of Ukraine, with around 11,000 troops present, according to Ukrainian and Western analysts.
The Kremlin has declined to comment.
"There are a lot of different arguments out there, both right and wrong," Kremlin spokesman Dmitry Peskov told the media on Friday.
"It's not worth commenting on every time," he said.
Ukraine's military also said on Friday its drones hit a major oil refinery in Russia's Volgograd region, causing explosions and a fire.
The military said in a statement that it would continue to target Russia's strategic infrastructure to reduce Moscow's forces' ability to continue its war in Ukraine.
A Ukrainian drone attack last week forced a refinery in Ryazan, southeast of Moscow, to suspend operations.
-AFP/ABC
