Pyongyang's Korean Central News Agency (KCNA) state media outlet reported on Wednesday that a missile tested on Tuesday had a hypersonic glide component, although this claim has not been independently verified.
The South Korean military had announced the North's launch of a missile on Tuesday, but have not officially specified the type, or how far it had flown.
South Korean President Moon Jae-in had ordered a "thorough analysis" of the test launch earlier on Wednesday, before the North's claims.
'Hypersonic' with fuel 'ampoule'
Hypersonic missiles are capable of traveling at least five times speed of sound, and are more difficult to track and intercept.
The KCNA report called the missile a Hwasong 8, saying that it has "great strategic significance," seeming to imply a nuclear capability.
It also said the test launch confirmed the stability and performance of the engine and the "ampoule" fuel system, which KCNA said it was testing for the first time. Ampoule is the Russian term for liquid-propellant missiles that can be fueled during production and then sent to the field in canisters. It means that soldiers do not need to fuel the missiles in the field, potentially during combat, before launch.
KNCA said Pak Jong Chon, a North Korean Marshal and a member of the politburo presidium, attended the launch; it did not mention leader Kim Jong Un.
According to KCNA, Pak "also noted the military significance of turning all missile fuel systems into ampoules."
North Korea's announcement comes after the United States said Tuesday it had successfully tested its own hypersonic missile system, and was moving ahead with plans to make the missiles operational by the US military.
Russia, China and other countries are also developing hypersonic weapons systems.
Meanwhile, South Korea launched a new homegrown submarine capable of firing ballistic missiles on Tuesday.
Tuesday's test also coincided with a meeting of North Korea's parliament, the Supreme People's Assembly, and the presentation of Volume 39 of a series of books on the purported life and achievements of former leader Kim Jong Il, who died almost 10 years ago
North Korea has recently resumed testing weapons in defiance of UN and US-led sanctions. At the close of the UN General Assembly late Monday in New York, Pyongyang's envoy insisted the North had a right to test weapons as a "deterrent."
Kim's influential sister, Kim Yo Jong, last week seemed to suggest that renewed peace talks with South Korea were possible, but only if Seoul abandoned "hostile policies," a term Pyongyang often uses to refer to international sanctions against North Korea and US-South Korean joint military activities.