BEIRUT (Reuters) - Lebanon s president has told foreign ambassadors that the country s prime minister Saad al-Hariri, who resigned suddenly last week in Saudi Arabia, has been  kidnapped  and must have immunity, a senior Lebanese official told Reuters on Saturday. President Michel Aoun has been convening high-level meetings with Lebanese politicians and foreign diplomats since Hariri resigned in a surprise broadcast from Saudi Arabia last week. Aoun made the remark in a meeting on Friday, the official said. 