North Korea has recently unveiled significant progress on its first nuclear-powered submarine, a development that has heightened tensions in the Indo-Pacific region. State media released images showing leader Kim Jong Un inspecting the vessel at a shipyard, describing it as an 8,700-ton-class nuclear-propelled submarine capable of carrying ballistic missiles.

This marks a potential advancement in Pyongyang's naval capabilities, with the hull appearing largely complete and coated in anti-corrosive paint.

The submarine, referred to as a "strategic guided missile submarine" or "strategic nuclear attack submarine," aims to bolster North Korea's nuclear deterrent. Analysts note that its size exceeds earlier diesel-electric models like the Sinpo-C class, which displace around 3,000 tons and carry fewer missiles.

Experts suggest the vessel could launch up to ten nuclear-capable missiles from underwater, complicating detection and interception efforts.

Construction appears advanced, with photographs indicating internal systems may already be installed, as submarines are typically built from the inside out. Moon Keun-sik, a submarine specialist at Hanyang University in Seoul, stated that the full hull display implies the submarine could undergo sea trials within months. North Korea first announced the project in 2021 as part of a broader weapons development plan, including hypersonic missiles and ICBMs.

Kim Jong Un linked the submarine's development to regional rivalries, condemning South Korea's push for its own nuclear-powered submarines, backed by U.S. President Donald Trump. He described Seoul's efforts as an "offensive act" that undermines North Korea's security and maritime sovereignty. Trump has expressed openness to sharing technology with South Korea to modernise its diesel-powered fleet, a move set to involve construction in Philadelphia.

No verified reports confirm Trump being "shocked" by the unveiling, though sensational headlines have amplified concerns in Washington. The U.S. has long viewed North Korean nuclear advancements as a threat to its homeland and allies, prompting sustained deterrence measures. Pyongyang's state media timed the reveal amid U.S.-South Korea exercises like Freedom Shield, followed by North Korean missile tests into the sea.

The submarine could provide North Korea with a survivable second-strike capability, allowing launches from stealthy underwater positions toward the U.S. mainland or allies. This escalates risks in the Indo-Pacific, where submarine-launched ballistic missiles challenge existing defences like THAAD. Questions persist over Pyongyang's ability to source nuclear propulsion technology under sanctions, with speculation of Russian assistance amid growing ties.

Experts warn that operational deployment would represent an "epoch-making" shift in North Korea's navy, enhancing its deterrence against perceived threats from the U.S., South Korea, and Japan. The vessel's potential for hypersonic glide vehicles further complicates missile defence strategies. Tensions remain high, with stalled denuclearisation talks since Trump's 2019 summit with Kim.

Agencies

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