ISTANBUL

North Korean leader Kim Jong Un said a plan by South Korea to develop nuclear-powered submarines with the US is a threat to stability in the region, calling it an “offensive act.”

Kim made the remarks during his inspection of an “8,700-ton nuclear-powered strategic guided missile submarine” under construction, the state-run Korean Central News Agency (KCNA) reported Thursday.

The North Korean leader said Seoul’s plan to build nuclear-powered submarines “will worsen the instability in the region of the Korean Peninsula” and stressed that Pyongyang regards it “as an offensive act severely violating its security and maritime sovereignty and a threat to its security that must be countered.”

Kim said that given the current situation, it is an “urgent task and indispensable option to further accelerate the radical development of the modernization and nuclear weaponization of the naval force” of North Korea.

The report also said that Pyongyang is developing a nuclear-powered submarine equipped with guided missiles, a project it first unveiled in March, citing a decision made at a party congress.

Kim also observed the test-firing of a “new-type high-altitude long-range anti-air missile” on Wednesday, KCNA reported Thursday, noting that the missile successfully hit a mock target at an altitude of 200 kilometers (124 miles).

In a separate report on Thursday, KCNA said that Russian President Vladimir Putin sent New Year’s greetings to Kim, thanking him for his ongoing military support for the war in Ukraine.

“The heroic entry of soldiers of the (North) Korean People's Army into the battles for liberating the Kursk region from occupiers and the subsequent activities of Korean engineers in the land of Russia clearly proved the invincible friendship and militant fraternity between the Russian Federation and the DPRK (North Korea),” the message said according to KCNA.

North Korea sent around 1,000 military engineers to Kursk in August to assist Russian forces in clearing mines laid during the fighting with Ukrainian troops.

The deployment followed an earlier dispatch of an estimated 15,000 North Korean combat troops to support Russia’s war effort, according to South Korea's spy agency, which claimed that Pyongyang has lost 2,000 troops in the war.