"The hypersonic missile system will reliably contain any rivals in the Pacific region that can affect the security of our state," Kim, who oversaw the launch, said in comments carried by KCNA.

The test-fire came as US Secretary of State Antony Blinken visited strategic ally South Korea, a fierce rival of the North, with whom it technically remains at war.

In a statement, Kim said the missile flew for 1,500 kilometres (930 miles) -- beyond the 1,100-kilometre (680-mile) figure given by South Korea's military -- and travelled at 12 times the speed of sound before landing in water.

"This is clearly a plan and effort for self-defence, not an offensive plan and action," Kim said.

However, he added that the performance of the missile system "can not be ignored worldwide," saying it can "deal a serious military strike to a rival while effectively breaking any dense defensive barrier."

"The development of the defence capabilities of the DPRK aiming to be a military power will be further accelerated," Kim said, using the acronym for the North's official name.

Blinken and his South Korean counterpart Cho Tae-yul condemned the launch at a joint news conference, where the outgoing US top diplomat said it showed the importance of deepening a three-way alliance with Japan.

Monday's test-fire was North Korea's first since US President-elect Donald Trump won his country's November election.

Its previous launch was in November, when it test-fired what it said was its most advanced and powerful solid-fuel intercontinental ballistic missile (ICBM).