North Korea says leader Kim Jong Un has visited a new facility to produce nuclear materials and announced plans to bolster the country’s nuclear forces “at an exponential rate."

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…