North Korean leader Kim Jong Un has vowed to bolster his nuclear weapons program in response to the U.S.’s enhanced security partnership with South Korea and Japan. Last year, the U.S. expanded bilateral military exercises with South Korean and trilateral training with South Korea and Japan.

Pyongyang has made clear its nuclear weapons are no longer negotiable but its strategy can be recalibrated depending on Washington’s approach.

The North Korean leader said the partnership poses a grave threat to his country and vowed to further bolster his nuclear weapons program.

Trump claims he knows Kim Jong-un better than anyone and discusses Xi currency Trump emphasizes his unique understanding of Kim Jong-un while addressing economic discussions with Xi Jinping.