North Korea has for the first time confirmed that it sent troops to fight for Russia against Ukraine.

Axar.az reports, citing BBC, in a report on state news agency KCNA, Pyongyang's military claimed its soldiers helped Russian forces "completely liberate" the Kursk border region, according to an order given by leader Kim Jong Un.

The decision to deploy troops was in accordance with a mutual defense treaty between Pyongyang and Moscow, KCNA said.

"They who fought for justice are all heroes and representatives of the honour of the motherland," Kim said according to KCNA.

North Korea and Russia demonstrated their "alliance and brotherhood" in Kursk, adding that a "friendship proven by blood" will greatly contribute to expanding the relationship "in every way".

It added that North Korea would support the Russian army again.

It should be noted that Russia's "Kremlyovskaya Tabakerka" channel reported that 8,500 North Korean soldiers were killed, and 11,000 others were injured in the Kursk region.