BEIRUT — Lebanon's outgoing prime minister has joined the opposition.
Saad Hariri made the announcement Monday during a ceremony marking the sixth anniversary of the assassination of his father, former Prime Minister Rafik Hariri.
Saad Hariri was ousted as prime minister last month in a dispute over the investigation into who killed his father.
An international tribunal set up to try his killers has yet to identify the perpetrators. But the tribunal is widely expected to accuse Hezbollah members of involvement in the killing. The Shiite militant group and its allies walked out of the previous government after Saad Hariri refused to denounce the tribunal.