A top South Korean official on Saturday said a US-South Korean military exercise would go ahead as planned next month, denying Pyongyang’s charges that holding it would breach an agreement made between US President Donald Trump and North Korean leader Kim Jong-un.“The nature of the exercise is not offensive … and is for strengthening the alliance,” Choi Jong-kun, the secretary for peace planning to South Korean President Moon Jae-in, told the Aspen Institute’s annual strategic forum.Later, Choi…