Kim's remarks follow the North's deployment of troops and weapons to help Russia during its more than three-year long offensive in Ukraine.

Video footage aired by state-run Korea Central Television on Thursday showed soldiers from artillery units firing shells towards the sea.

Kim is seen looking through binoculars at an observation post, flanked by two military officials, but the location for Wednesday's contest was not disclosed.

He urged the soldiers to be ready "for real war" at "anytime" and be capable of "destroying the enemy in every battle", the Korean Central News Agency reported in an English dispatch.

South Korean and Western intelligence agencies have reported Pyongyang sent more than 10,000 soldiers to Russia's Kursk region last year, along with artillery shells, missiles and long-range rocket systems.

Around 600 North Korean soldiers have been killed and thousands more wounded fighting for Russia, Seoul has said.

Kim offered Moscow his full support for its war in Ukraine during recent talks with Russian Foreign Minister Sergei Lavrov, state media reported previously.

The two heavily sanctioned nations signed a military deal last year, including a mutual defence clause, during a rare visit by Russian President Vladimir Putin to Pyongyang.