North Korean leader Kim Jong Un inspects the construction status of a nuclear submarine. Pyongyang, KCNA/Yonhap News

North Korean leader Kim Jong Un inspected the construction site of a new nuclear-powered submarine currently being built and denounced South Korea's pursuit of nuclear submarines as an "aggressive act that severely infringes upon our state's security and maritime sovereignty."

The Korean Central News Agency (KCNA) reported on March 25 that Kim supervised the construction project of an 8,700-ton "nuclear-powered strategic missile submarine" on-site.

Kim stated, "The plan for South Korea's development of nuclear submarines, recently agreed upon with Washington at Seoul's request, will further destabilize the Korean Peninsula. We consider this an aggressive act that severely infringes upon our state's security and maritime sovereignty, and a security threat that must be countered."

He emphasized that there will be "not an iota of change" in North Korea's "state security guarantee policy and principle of countering the enemy," adding, "When the enemy infringes upon our strategic sovereign security, they must pay a price, and if they attempt military options, they must be made to realize without doubt that they will face indiscriminate retaliatory attacks."

Kim also asserted, "Further strengthening our nuclear shield, which is the guarantee of absolute security, and solidifying its irreversible status is the noble mission and duty of our generation."

He reiterated North Korea's stance against denuclearization, stating, "The determination of our party and the government of the republic to ensure the permanent peace environment and absolute security of the state through the formation of nuclear forces that the enemy cannot help but fear will remain unwavering."

He further evaluated the new nuclear submarines being built by North Korea as a "historic, significant change that makes both ourselves and even the enemy more confident in our war deterrence capabilities," and a "significant component of nuclear war deterrence."

Given North Korea's use of terms such as "nuclear-powered strategic missile submarine" and "nuclear strategic attack submarine" on this occasion, it appears to be a claim that they are building submarines equipped with strategic guided missiles powered by nuclear fuel. North Korea had previously revealed in March that the construction of a "nuclear-powered strategic missile submarine" was being pursued in accordance with the decisions of the 8th Congress of the Workers' Party of Korea.

The KCNA reported that the regime emphatically declared its will and strategic and tactical policy to continuously and strongly pursue the "nuclear armament of the navy," which is interpreted as a desire to acquire sea-based nuclear delivery capabilities.

In this regard, Kim stated, "The attack destroyers and nuclear submarines currently under construction will dramatically enhance the combat power of our fleet and contribute to the defense of our state's strategic sovereign security." He also mentioned accelerating the construction speed of various surface and underwater vessels and integrating "different attack weapon systems" into them.

Furthermore, the KCNA reported that he gained a concrete understanding of the research and development status of newly developed "underwater secret weapons" and revealed strategic plans related to the reorganization of naval forces and the creation of new units.