The potential for war is increasing every day but armed conflict is not the only solution, he told a defence forum.
News about the launch comes within days of North Korea launching a new type of intercontinental ballistic missile (ICBM).
It was the country's third intercontinental ballistic missile (ICBM) test, but the first of what North Korea is calling its Hwasong-15 missile.
Pyongyang has been under United Nations sanctions since 2006 over its ballistic missiles and nuclear programs. Pyongyang conducted its first nuclear test in September.
The country's state media announced the test on Wednesday, hours after leader Kim Jong Un ordered the launch of the Hwasong-15 missile, which reached the highest altitude ever recorded by a North Korean missile.
Seoul's Korean Times quoted a defence source, who is aware of the latest development, as saying that the brigade's mission will be to eliminate key North Korean authorities if there is a full-fledged conflict in the region.
Washington is battling to maintain global solidarity in the face of the North nuclear threat after Russian Federation warned that sanctions have failed and China sidestepped talk of an oil embargo.More news: Disney's Live-Action 'Mulan' Casts Liu Yifei in Title Role
However, he added: "It is impossible for us not to condemn the provocations by our American colleagues".
North Korea on Tuesday broke a two-month lull in weapons testing. It has been set up under the South Korean army's Special Warfare Command.
The statement came after Yonhap News reported that six US Raptor stealth fighters planes arrived in South Korea on Saturday for a joint air drill named "Vigilant Ace" scheduled for December 4 to 8.
The tension in the Korean Peninsula is extremely high.
"The US and South Korean puppet warmongers would be well advised to bear in mind that their DPRK-targeted military drill will be as foolish as an act precipitating their self-destruction", it said.
Commenting that the planned manoeuvre would be the "largest-ever" such drill, a spokesman for the North's Ministry of Foreign Affairs said in a statement Saturday: "The Trump team is begging for nuclear war by staging an extremely unsafe nuclear gamble on the Korean peninsula".
But analysts remain unconvinced that it has mastered the advanced technology to allow the rocket to survive re-entry to the Earth's atmosphere.