North Korea’s senior envoy for U.S. affairs renewed a threat to call off a planned summit with President Donald Trump and warned that Pyongyang could “make the U.S. taste an appalling tragedy it has neither experienced nor even imagined.”

In its most direct language aimed at Washington following a recent rapprochement between the two countries, Choe Son Hui, the North’s vice minister of foreign affairs, said if the June 12 talks were called off, the U.S. could instead face off with North Korea in a “nuclear-to-nuclear showdown.”

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