North Korea said on Monday it had developed a new control system for a multiple rocket launcher that would lead to a "qualitative change" in its defence capabilities.
Pyongyang's Academy of Defense Science successfully carried out a "ballistic control test firing of 240-mm caliber multiple rocket launcher shells" on Saturday to develop a "controllable shell and ballistic control system" for the launcher, state news agency KCNA reported.
The new rocket launcher would now be "reevaluated" and its battlefield role "increased", KCNA said, AFP reported.
Nuclear-armed North Korea this year declared South Korea as its "principal enemy", closing agencies dedicated to reunification and outreach, and threatening war over "even 0.001 millimetres" of territorial infringement.
Leader Kim Jong Un repeated on Friday that Pyongyang would not hesitate to "put an end" to South Korea if attacked, calling Seoul the North's "most dangerous and first enemy state and invariable arch-enemy".
In January, North Korea fired an artillery barrage near two South Korean border islands, prompting a live-fire drill by the South and evacuation orders for residents.
Kim has also ramped up weapons testing, including this year's launch of a flurry of cruise missiles, which analysts said the North could be supplying to Russia for use in Ukraine.
South Korean President Yoon Suk Yeol has vowed a strong response if Pyongyang attacks, calling on his military to "act first, report later" if provoked.
The hawkish Yoon has bolstered defence cooperation with the United States and Japan since coming to office in 2022, including expanding joint drills, to counter Pyongyang's growing threats.