In this photo provided by the North Korean government, its leader Kim Jong Un, with his daughter, believed to be named Kim Ju Ae, inspects the test-firing of ballistic missiles from an undisclosed location in North Korea.

North Korean leader Kim Jong Un has said he will unveil plans to further strengthen the country’s nuclear forces at an upcoming ruling party congress, state media reported on Wednesday, following a fresh missile launch that he said would inflict “excruciating mental agony” on Pyongyang’s enemies.According to state-run Korean Central News Agency (KCNA), Kim made the remarks while overseeing a missile test on Tuesday. The congress of the ruling Workers’ Party, expected in the coming weeks, will be the first such meeting in five years and is likely to set North Korea’s political and military direction. Kim said the gathering “will clarify the next-stage plans for further bolstering up the country’s nuclear war deterrent,” as quoted by news agency AFP.KCNA said Kim watched the test-firing of a “large-caliber” multiple rocket launcher that fired four missiles, accompanied by senior officials and his young daughter, widely believed by analysts to be named Kim Ju Ae. Photos released by state media showed the pair observing the launch together. Kim said the test would pose a “serious threat” to forces seeking military confrontation with North Korea, adding that it was significant in improving the effectiveness of the country’s strategic deterrent.The missiles were fired towards the Sea of Japan, with Japanese media citing defence sources saying two landed outside Japan’s Exclusive Economic Zone. As per AFP, the rockets hit a target about 358.5 kilometres away.Kim said boosting military capability remains the ruling party’s core line and that the congress would be used to announce the next phase of nuclear development. Analysts quoted by AFP said Kim is expected to declare that North Korea’s nuclear capability has reached a new peak, with a focus on maximising operational readiness.The test marked North Korea’s second weapons launch this month and came amid heightened regional tensions involving the United States and South Korea. Pyongyang routinely denounces joint US-South Korea military drills as invasion rehearsals, while Washington continues to station troops in the South as a deterrent against the nuclear-armed North.