The Democratic People's Republic of Korea (DPRK) revealed for the first time a nuclear-powered submarine under construction, a weapons system that could challenge South Korea and the US.

State media on Saturday released images of what it described as "a nuclear-powered strategic guided missile submarine," following leader Kim Jong Un’s visits to major shipyards where warships are built.

The Korean Central News Agency (KCNA) did not provide further details about the submarine but noted that Kim was briefed on its construction.

According to Moon Keun-sik, a South Korean submarine expert at Seoul’s Hanyang University, the naval vessel appears to be a 6,000-ton-class or 7,000-ton-class submarine capable of carrying around 10 missiles. He explained that the use of the term "strategic guided missiles" suggests it would be equipped with nuclear-capable weapons.

“It would be absolutely threatening to us and the US,” Moon said.

US National Security Council spokesperson Brian Hughes stated, "We’re aware of these claims and do not have additional information to provide at this time," further explaining that "The US is committed to the complete denuclearization of North Korea."

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A nuclear-powered submarine was part of a lengthy list of advanced weaponry that Kim Jong Un promised to introduce during a major political conference in 2021, aiming to counter what he described as escalating US-led military threats.

Other weapons included solid-fueled intercontinental ballistic missiles, hypersonic weapons, spy satellites, and multi-warhead missiles. Since then, the DPRK has conducted a series of testing activities to develop these capabilities.

The DPRK's enhanced ability to launch missiles from underwater is a concerning development, as it makes it harder for its rivals to detect such launches in advance.

The DPRK is believed to have around 70-90 diesel-powered submarines, making it one of the world’s largest fleets. However, most of these are aging vessels, capable only of launching torpedoes and mines, not missiles.

DPRK threatens 'toughest response' to US, South Korea military drill

This comes after the DPRK issued a warning to South Korea on Friday, threatening a harsh response if Seoul holds its joint military drills with Washington in the coming weeks.

South Korea and the United States will pay a "horrible" price, said a commentary on the KCNA, emphasizing that “The enemy states will have to pay dearly for their foolish and reckless war drills, which will lead to a self-defensive, fair, and square, threatening, toughest response from North Korea."

The DPRK statement comes a day after the South Korean and US militaries announced the joint military drill Freedom Shield, which will kick off on March 10 for 11 days, and includes computer-simulated drills and on-field training.

“The Freedom Shield has repeatedly undergone its worst modifications, fully equipped with all malicious signs. This will soon bring a storm of aggravating the security situation to the Korean Peninsula,” KCNA noted, adding that the military exercise is an infringement on the DPRK's sovereign rights and interests and risks regional instability.

KCNA went on to criticize the planned escalation of military drills between South Korea and the United States from 10 in 2024 to 16 in 2025, stressing that Pyongyang's enemies' "war frenzy" is moving toward a dangerous level.

The DPRK emphasized that it will be left with no choice but to "renew" its "strategic deterrence" if the United States continues its "military muscle-flexing", considering the counteraction inevitable.

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