By Ju-min Park and Joyce Lee SEOUL (Reuters) -North Korean leader Kim Jong Un said his country needed to rapidly expand its nuclear armament and called U.S.-South Korea military exercises an "obvious expression of their will to provoke war,

North Korea’s leader threatens to speed up Pyongyang’s nuclear arsenal expansion over a sign of ‘hostile intent’.

North Korea must grow its nuclear arsenal, Kim Jong-un has said, as he hit out at joint military drills between the US and South Korea.