In a surprise move, Lebanese Prime Minister Saad Hariri today resigned from his post during a trip to Saudi Arabia.<br/><br/>The resignation plunged the country into uncertainty amid heightened regional tensions. <br/><br/>In a televised address from Riyadh, Hariri fired a vicious tirade against Iran and the Lebanese Hezbollah group for what he said was their meddling in Arab affairs. <br/><br/>Hariri was appointed Prime Minister in late 2016 and headed a 30-member national unity cabinet that included the Shiite militant Hezbollah.