South Korea's top military commander said Tuesday North Korea could wage war if its regime is threatened or if it misjudges the security situation on the Korean Peninsula.

Navy Adm. Choi Yun-hee, the head of the Joint Chiefs of Staff (JCS), warned of the possibility that the North could make a bad decision when asked by lawmakers under what condition a war could occur on the peninsula.

North Korean leader Kim Jong-un could opt for war if his regime is threatened, the balance of military power changes between the two Koreas or alliance between Seoul and Washington is weakened, Choi said.

"Considering the recent situation, the North Korean regime is different from the one during the Korean War," the former Navy chief said during the first parliamentary audit since taking the top commander post last week.

The Korean War began on June 25, 1950 after the communist North invaded South Korea to unify the Korean Peninsula divided along the 38th parallel.

According to several documents, then North Korean leader Kim Il-sung, the current ruler's grandfather, went ahead with a full-out war after both China and Russia approved his decision and promised to send reinforcements if needed.

When asked how to handle the young leader who vowed to reunify the two Koreas by force in the next three years, Choi pledged to maintain high military readiness to deter North Korean threat.

"Besides the rhetorical threats, the North Korean military has continuously sought to enhance capabilities through drills," Choi said. "We will use all forces to deter (provocations), mobilizing U.S. forces if needed."

Kim said the North sent propaganda leaflets through the border nine times this month alone, which were collected by South Korean soldiers at the front-line units.

He also said North Korean patrol ships crossed the western maritime border, called the Northern Limit Line (NLL), nine times in October, while fishing boats occasionally operated south of the line.

Choi also pledged to beef up South Korean forces' deterrence capabilities as Pyongyang has made progress in its weapons program by firing off a long-range rocket last December and conducting a third nuclear test in February.

Military analysts believe the latest move is aimed at developing technology to miniaturize a nuclear warhead small enough to be launched on an intercontinental ballistic missile.

The two Koreas still technically remain at war as the three-year conflict ended in a cease-fire and no permanent peace treaty was signed by the combatants.

(Yonhap News)