Kim Jong-un has called the nuclear armament of North Korea's navy an urgent national agenda as he supervises a submarine-launched cruise missile test.
North Korea has tested a newly developed submarine-launched cruise missile (SLCM), accelerating its navy's nuclear armament, state media reports.
Leader Kim Jong-un supervised Sunday's test of the missile, called "Pulhwasal-3-31".
The missile is identical to the strategic cruise missiles the North said on Wednesday were under development.
State news agency KCNA and the official Rodong Sinmun newspaper said the missiles flew above the sea off the country's east coast for 7421 seconds and 7445 seconds and hit an unspecified island target, indicating the flight time exceeded two hours.
Kim called the test a success, KCNA said, "which is of strategic significance in carrying out the plan ... for modernising the army which aims at building a powerful naval force".
North Korea says it has tested a newly developed submarine-launched cruise missile.
South Korea's military said on Sunday the North fired multiple cruise missiles off its coast but did not provide details.
The North said on Wednesday it had tested a new strategic cruise missile, indicating it was designed to carry a nuclear warhead, but at the time did not mention it was being developed for submarine launch.
State media photographs published on Monday showed a missile launching into a cloudy sky from the water trailed by a plume of smoke which obscures the type of platform it was being fired from.
North Korea's ballistic missiles are typically more controversial and are explicitly banned under United Nations Security Council resolutions.
But analysts have said intermediate-range cruise missiles are no less a threat than ballistic missiles and are a serious capability for North Korea.
In recent months, the North has tested an array of weapons that include ballistic missile systems that are under development and an underwater drone.
Kim separately inspected the construction of a nuclear submarine and discussed issues related to the manufacturing of other types of new warships, KCNA said but gave no details.
In 2023, North Korea launched what it called its first operational nuclear attack submarine, which analysts said appeared to be a modified from an existing submarine and likely designed to carry ballistic and cruise missiles.
There was scepticism over the real-world utility of such a vessel, especially compared to the more advanced land-based missile systems, because its diesel propulsion generates noise and is limited in range, according to weapons experts.
Kim said at the time the country would accelerate the program to build nuclear-powered submarines.