North Korean leader Kim Jong Un has vowed to strengthen his country’s nuclear operations going forward.
In the aftermath of more missile tests this week, Mr Kim said there is no need to have dialogue with North Korea’s adversaries.
An intermediate-range ballistic missile (IRBM) sent over Japan on Tuesday was a newly-developed missile aimed at delivering stronger and clearer warning to North Korea’s enemies, according to the KCNA state news agency.
Over the last two weeks Mr Kim has overseen and guided the country’s tactical nuclear operation unit training, the report said.
As well as the missile launch on Tuesday, the South Korean military said a pair of short-range ballistic missiles were detected overnight on Saturday, flying towards its eastern waters.
North Korea has conducted seven rounds of weapons tests over the past couple of weeks.
It comes as the United States and South Korea conducted naval drills off the Korean Peninsula’s east coast involving nuclear-powered aircraft carrier USS Ronald Reagan.