"North Korea is working on boosting capabilities and variety of its weapons. We must introduce such a missile defence system that could respond to all types of challenges", Iwaya said, as quoted by the Kyodo news agency.
On Wednesday, North Korea fired two short-range ballistic missiles that flew 250 kilometres (155 miles) toward the Sea of Japan. North Korea’s state-run KCNA news agency has reported that Pyongyang test-fired a new large-calibre multiple-launch guided rocket system under the supervision of the country's leader, Kim Jong-un.
Moreover, last week, Pyongyang test-fired two other projectiles that also appeared to be short-range missiles in what were the first missile tests by North Korea since US President Donald Trump met with Kim at the demilitarized zone in June.