North Korea say dem don test one new solid-fuel intercontinental ballistic missile – di kontri "most powerful" missile to date.

State media hail Thursday launch, wey lead to quick evacuation order for Japan, one "miraculous success".

Solid-fuel missiles fit dey fired more quickly dan liquid-fuel ones wey make dem harder to intercept.

But analysts say dem no dey without downsides.

South Korea maintain say di North go need more time to develop one fully operational solid-fuel ICBM.

Dis be di first time di North don test-fire one solid-fuel ICBM afta years wey dem test solid-fuel short-range missiles.

Dem don test many ICBMs, but those ones dey powered by liquid propellant.

Dis one ghas dey fuelled directly ahead of launch - one process wey fit take hours.

Experts describe am as breakthrough for Pyongyang weapons programme.

As solid-fuel ICBMs come ready-fuelled, and go therefore allow North Korea to strike di US wit far less warning.

South Korea Defence Ministry on Friday say di technology no dey new, and describe North Korea test on Thursday as "middle step" for developing one full-fledged solid-fuel ICBM system.

North Korean leader Kim Jong Un, wey supervise di test wit im daughter, wife, and sister, bin tok say say di test go make rivals "suffer from extreme fear and anxiety".

E also tok say di test-fired weapon, wey dem sabi as Hwasong-18, support di North aggressive military strategy.

Di launch cos gbege for Japan

Thursday morning launch primary aim na to "confam di performance of di high-thrust solid-propellant multistage motors.

Di stage separation technology and how dem rely on many functional control systems".

Di state Korean Central News Agency tok for dia report on Friday.

Di launch bin cause confusion for northern Japan, wia evacuation order dey issued and den take am back within 30 minutes.

Schools for Japan Hokkaido island delay dia start times and some train services dey suspended.

Authorities for Japan, South Korea and di US strongly condemn di move, wey come days afta tori bin fly say Mr Kim order im military to adopt one "more practical and offensive" manner for war deterrence.

'No be surprise'

Analysts say di North launch of new, more powerful weapon no come as surprise.

"Given say North Korea bin don dey test large diameter solid rocket motors for di Pukguksong-series (one range of medium-range missiles, including submarine-launched missiles) for many years, E don dey clear say since 2020, one test like dis fit don come any time," Jeffrey Lewis wey be director of di East Asia Non-proliferation Program for di James Martin Center for Non-proliferation Studies for California.

Long-range solid fuel missiles fit dey operationally superior to dia liquid counterparts, but dey harder to maintain and store.

Ankit Panda, one nuclear weapons specialist at di Carnegie Endowment for International Peace tok.

Dem dey more sensitive to humidity, temperature and physical stress, and fit degrade over years inside storage.

Dis na important week for North Korea as dem celebrate Mr Kim 11th year for power - di kontri fit try mark dis anniversaries wit displays of military progress.

North Korea don dey work to increase dia nuclear arsenal and build ever-more sophisticated weapons.

Di kontri don also criticise joint military exercise between di US and South Korea, dem accuse dem say dem dey increase tensions.

Di latest missile launch also come two days bifo di birthday of North Korea founding leader Kim Il Sung - di biggest annual holiday on di kontri calendar.