GENEVA President Bashar Assad and his family have no role in the future Syria, US Secretary of State Rex Tillerson said on Thursday."The United States wants a whole and unified Syria with no role for Bashar Assad in the government," Tillerson told reporters in Geneva on the last leg of a week-long trip. "The reign of the Assad family is coming to an end. The only issue is how that should that be brought about."Tillerson said the only reason Assad's forces had succeeded in turning the tide in the more than six-year war was "air support they have received from Russia". Iran, the other main ally of Damascus, should not be given credit for the defeat of Islamic State, as it was a "hanger-on," he said.