The Korean Central News Agency said that Kim inspected the country's latest strategic weapons development at a test facility of the national defense science institution. It didn't reveal the weapon's type or name.
"Comrade Kim Jong Un visited the national defense science institution's test facility and instructed testing of the state-of-the-art strategic weapon," it said.
The report comes after a U.S. think tank revealed an undeclared missile base in North Korea that is still active despite its denuclearization pledges. The Center for Strategic and International Studies' Beyond Parallel initiative on Korean issues said on Monday that the Sakkanmol Missile Operating Base in North Hwanghae Province show signs of use.
Denuclearization talks between the U.S. and North Korea have shown no signs of making a progress to dismantle North Korea's nuclear program. A meeting that was scheduled for last week in New York between U.S. Secretary of State Mike Pompeo and his North Korean counterpart was postponed without an immediate plan to resume.
For inspection, Kim was accompanied by major military officials, including Choe Ryong-hae, a close aide to Kim and vice-chairman of the central committee of the Workers' Party of Korea, North Korea's ruling political party.
Kim said that a new weapons system was born after many years of development.
"Our military scientists and workers have done a great job to enhance our defense capabilities," Kim was quoted as saying in the KCNA report.
Kim said he was hugely satisfied with the weapons development that makes a "turning point" in enhancing combat power of the country.
The last time Kim was seen watching a weapon test was November last year when he inspected a test-fire of an inter-continental ballistic missile Hwasong-15.
South Korean military presumed the weapons system to be a long-range artillery gun system under its monitor, South Korean Yonhap News said, citing an anonymous military source.
The unification ministry also said Kim Jong Un has been conducting inspections on military weapons system intermittently and it assumes what the North calls an advanced strategic weapon to be conventional weapon. But a ministry official said it needs a confirmation to why they called it "advanced."