North Korea has unveiled a new facility to produce weapons-grade nuclear material as the South Korean military said it was closely coordinating with the United States to monitor Pyongyang's nuclear activities.

North Korean leader Kim Jong-un has visited a newly launched nuclear material production facility, vowing to "exponentially" strengthen the country...

Of the planned increase, North Korean leader Kim Jong Un said: "This signifies an amazing, successful change that is beyond rhetorical description, a historic event that has set…