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President Trump has pulled out of a historic summit in Singapore with North Korean Leader Kim Jong Un, which had been scheduled for June 12, calling it "a truly sad moment in history."

In an open letter, Trump told Kim "we greatly appreciate your time, patience, and effort with respect to our recent negotiations" and that "I was very much looking forward to being there with you," but that "it is inappropriate, at this time, to have this long-planned meeting" due to increasing tensions between the parties. A North Korean vice minister of foreign affairs called Vice President Mike Pence "ignorant" and "stupid" on Thursday for comparing North Korea to Libya, and warned Kim would cancel the summit if the U.S. didn't stop its threats.

Read the letter in full below. Jeva Lange