Vice President Johnson had remained at the hospital while President Kennedy was worked on by the doctors, despite efforts by the Secret Service agents urging him to return to Washington immediately out of concern for his safety. Special assistant O'Donnell informed Johnson that Kennedy was dead at approximately 1:20 p.m. CST. He advised Johnson to return to Love Field immediately and fly to Washington on the presidential plane, rather than on Air Force Two, since it had better communications equipment. When he was informed that Mrs. Kennedy refused to leave without her husband's body, Johnson said that he would not leave Dallas without her. He waited for her on Air Force One. From the plane, Johnson telephoned Attorney General Robert F. Kennedy, who advised him to take the oath of office before takeoff. Federal Judge Sarah T. Hughes was called to the plane and administered the oath at 2:38 p.m. CST. Upon arrival at Andrews Air Force Base, President Johnson told the nation of Kennedy's assassination and death over television and radio.