UPDATE 1-U.S. envoy Biegun still believes North Korea can decide to denuclearize

U.S. Special Representative for North Korea Stephen Biegun said on Wednesday there had been no concrete evidence that North Korea had made a decision to give up its nuclear weapons, but he still believed Pyongyang could make this choice.Biegun made the remarks in prepared testimony presented to the Senate Foreign Relations Committee in his nomination hearing for the State Department's No. 2 post.Biegun has led U.S. efforts to try to persuade North Korea to denuclearize since last August, with li