North Korean leader Kim Jong-un has reportedly vowed to increase the production of nuclear warheads "exponentially" in a key party meeting.

According to the North's official Korean Central News Agency (KCNA) on Sunday, Kim highlighted the need to bolster the country's nuclear arsenal during a plenary meeting of the ruling Workers' Party the previous day.

Kim reportedly said that the current situation, where South Korea has become the North's undoubted enemy, highlights the importance and need of mass-producing tactical nuclear weapons and requires an exponential increase in the country's nuclear arsenal.

Kim also said that the North's nuclear force considers it as the first mission to deter war and guard peace and stability; however, if it fails to deter, it will carry out its second mission, which will not be for defense.

The remarks clearly indicate the North's intent to use nuclear weapons as a means of attack in case of armed conflict.

The KCNA said that Kim also presented the task of developing another intercontinental ballistic missile (ICBM) system with a rapid nuclear counterattack capability as its basic mission. The ICBM appears to refer to a solid-fueled ICBM.