North Korea leader Kim Jong Un says it has launched a nuclear attack submarine against US

North Korean leader Kim Jong Un says the sub is "a symbol of our revolutionary power to strike fear into the hearts of our despicable enemies". Photo / AP

North Korea says it has launched a nuclear attack submarine it has been developing for years, a step leader Kim Jong Un described as crucial in his efforts to build a nuclear-armed navy to counter the United States and its Asian allies.

The North’s official Korean Central News Agency said the vessel – named Hero Kim Kun Ok – is designed to launch tactical nuclear weapons from underwater. It did not specify the number of missiles it could carry and fire.

In his speeches at the launching ceremony on Wednesday and an onboard inspection on Thursday, Kim expressed satisfaction that the country has acquired its own nuclear attack submarine to counter the advanced naval assets of the US, the news agency said. In July, the US docked a nuclear-capable ballistic missile submarine in South Korea for the first time since the 1980s.

Kim said North Korea was also pursuing a nuclear-propelled submarine and planned to remodel its existing submarines and surface vessels so they could handle nuclear weapons. He described the building of a nuclear-capable army as an “urgent task”.

Based on Kim’s comments and photos by North Korean state media, it’s likely the new submarine was the same one Kim inspected in 2019 while it was under construction. Experts assessed it then as an effort to convert an existing Romeo-class submarine. The boat appears to have at least 10 launch tubes – four of them larger than the other six – that are possibly designed for ballistic and cruise missile launches.

North Korea had previously been testing a variety of missiles designed to be fired from submarines as it pursued an ability to conduct nuclear strikes from underwater. In theory, this would bolster its deterrent by ensuring a survivable capability to retaliate after absorbing a nuclear attack on land.

Ballistic missile submarines would also add a maritime threat to the North’s growing collection of solid-fuel weapons fired from land vehicles that are designed to overwhelm missile defences in South Korea and Japan. The two key US allies station tens of thousands of US troops in the region.

It would take considerable time, resources and technological improvements for the heavily sanctioned North to build a fleet of submarines that could travel quietly in seas and reliably execute attacks, analysts say.

“The nuclear attack submarine, for decades a symbol of aggression against our republic, has now become a symbol of our revolutionary power to strike fear into the hearts of our despicable enemies,” KCNA quoted Kim as saying.

He insisted that the submarine would be just as “daunting” to his enemies as the nuclear-propelled submarine North Korea plans to acquire in the future.

“In submarines, technical aspects such as the power system, submergence speed and the level of navigational equipment are all very important and would generally define [the vessels’] operational capabilities, but nothing is more important than the type of weaponry that could be installed,” he said.

North Korea previously had only one known submarine capable of firing a missile, but that vessel has a single launch tube and analysts considered it a test platform, rather than an active operational weapons system.

North Korea has an estimated about 70-90 diesel-powered submarines in one of the world’s largest submarine fleets. But they are mostly ageing ones capable of launching only torpedoes and mines, not missiles.

The report about the new submarine came amid speculation that Kim is preparing to visit Russia soon for a meeting with President Vladimir Putin that could focus on North Korean arms sales to refill Russian reserves drained by its war on Ukraine.

In exchange for providing Russia with artillery shells and other ammunition, North Korea could seek badly needed economic aid and advanced weapons technologies, including those related to submarine-launched ballistic missile systems, intercontinental ballistic missiles and military spy satellites, analysts say.

KCNA said the launching of the new submarine was timed for the 75th anniversary of the country’s founding, which falls on Saturday and is due to be marked by festivities, including a paramilitary parade.