It was the first time since November the North's leader has overseen a weapons testing, and the visit to the testing center came a day after he visited an air force unit.

"Saying that the completion of the development of the weapon system serves as an event of very weighty significance in increasing the combat power of the People's Army, he noted that it is a very good thing that the field of national defense science has waged a dynamic struggle for attaining core research goals," the KCNA said of Kim.

"After watching the power of the new-type tactical guided weapon, he pointed out that our national defense scientists and workers in the field of the munitions industry performed another great work in increasing the country's defense capabilities," the KCNA said.

Kim also set the "phased and strategic goals" for maintaining his country's munitions production, putting national defense science and technology on a "cutting edge level," and ordering "detailed tasks and ways to attain them."

Experts said the new weapon could be a newly developed short-range guided or cruise missile. They also said Kim's attendance at the test-firing could be aimed at sending a warning message to the United States without becoming overly provocative.

"Kim is trying to make a statement to the (Donald) Trump Administration that his military potential is growing by the day, and that his regime is becoming frustrated with Washington's lack of flexibility in recent negotiations," said Harry Kazianis, director of Korean studies at the Center for the National Interest, in an emailed comment.

The test-firing came after Kim suggested a year-end deadline for denuclearization negotiations following the breakdown of his February summit with Trump in Vietnam.

February's summit between Kim and Trump fell apart as they failed to find common ground over how to match Pyongyang's denuclearization steps with Washington's sanctions relief.

On Wednesday, Pyongyang's media said that the North Korean leader visited an air force unit and reviewed a flight exercise in his first public inspection of military activities in five months. (Yonhap)