North Korean leader Kim Jong Un has observed the test-firing of strategic cruise missiles, state media reported.
The test came as the US and South Korean militaries kicked off major annual drills which the North views as an invasion rehearsal.
The North’s report on missile tests came three days after the leaders of the US, South Korea and Japan held their first stand-alone trilateral summit and agreed to increase their cooperation on their ballistic missile defences to counter North Korea’s evolving nuclear and missile threats.
During an inspection of a navy flotilla on an unspecified date, Mr Kim boarded a patrol ship to review its weapons and preparations for combat, according to the official Korean Central News Agency (KCNA).
It said Mr Kim later watched the ship’s personnel conduct a drill of launching “strategic” cruise missiles – a word implying the weapons were developed to carry nuclear warheads.
A state media photo showed him watching a soaring missile from the patrol ship from another place, not on the vessel.
KCNA said the missiles hit designated targets without any errors, demonstrating the ship’s readiness and attack capability.
Mr Kim said he would bolster efforts to build powerful warships and modernise shipboard and underwater weapons systems for the North’s navy.
He called for the country’s sailors to build “overwhelming ideological and spiritual strength”, saying that is more important than numerical or technical superiority of weapons, according to KCNA.
South Korea’s Joint Chiefs of Staff said in a statement North Korea’s report on its cruise missile tests contained “an exaggeration” and was “not consistent with the facts”.
It said South Korea’s military will maintain firm readiness based on its capacity to overwhelmingly defeat potential North Korean provocations.
Leif-Eric Easley, a professor at Ewha University in Seoul, said: “North Korea’s naval cruise missile may appear technologically behind but is still a real threat.
“The latest test shows Pyongyang’s intention of attacking South Korea from many angles if it believes the Kim regime is at risk.”
Launches from North Korea’s huge stockpile of ballistic missiles are prohibited by UN Security Council resolutions. Its cruise missile tests are not banned, but they still pose a threat because they fly at a lower altitude to avoid radar detection.
Analysts say North Korea aims to use cruise missiles to strike incoming U.S. warships and aircraft carriers in the event of conflict.
North Korea was widely expected to resume weapons tests in reaction to the US-South Korean military training that began Monday for an 11-day run.
The Ulchi Freedom Shield training is a computer-simulated command post exercise. The US and South Korean militaries said they also plan conduct large-scale field exercises as well.
North Korea in past years has slammed major US-South Korean drills as practice for an invasion and has responded to them with missile tests.
American and South Korean officials maintain the exercises are defensive in nature and they have no intention of attacking the North.