The letter kicked off a day of mixed messages by the president, who declared hours later, "I really believe Kim Jong Un wants to do what's right." After that, a senior White House official said the North lacked judgment and had reneged on its promises ahead of the summit. Trump said from the White House that a "maximum pressure campaign" of economic sanctions and diplomatic isolation would continue against North Korea — with which the U.S. is technically still at war — but he added that it was possible the summit could still take place at some point.