IRAN'S SUPREME LEADER HAS OPENED THE DOOR TO NEGOTIATIONS WITH THE U-S OVER THE NATION'S NUCLEAR PROGRAM. IRAN'S LEADERS TOLD ITS CIVILIAN GOVERNMENT THAT THERE WAS QUOTE 'NO HARM" IN ENGAGING WITH THE "ENEMY." BUT EXPERTS NOTE - THEIR COMMENTS MIRROR THOSE AROUND TEH TIME OF IRAN'S 2015 NUCLEAR DEAL WITH WORLD POWERS. WHICH SAW TEHRAN ROLL BACK ON THE NUCLEAR PROGRAM IN EXCHANGE FOR LIFTING ECONOMIC SANCTIONS. THE U-S STATE DEPARTMENT SAYS IT WILL JUDGE IRAN'S LEADERSHIP BY THEIR ACTIONS NOT WORDS. A TOP OFFICIAL IN THE BIDEN ADMINISTRATION IS IN BEIJING, TRYING TO THAW U.S. RELATIONS WITH CHINA. NATIONAL SECURITY ADVISER JAKE SULLIVAN IS MEETING WITH CHINA'S FOREIGN MINISTER. HE ARRIVED YESTERDAY AND ADDITIONAL MEETINGS WILL TAKE PLACE THROUGH THURSDAY. NO MAJOR ANNOUNCEMENTS ARE EXPECTED. THE STATED GOAL OF THE TALKS IS SIMPLY TO KEEP THE LINES OF COMMUNICATION OPEN -- THOUGH IT'S POSSIBLE PRESIDENT BIDEN AND CHINA'S XI JINPING COULD HOLD ONE FINAL áSUMMITá BEFORE PRESIDENT BIDE