Hariri's speech came amid a state of intense tension between Saudi Arabia and Iran, a year after he was appointed the prime minister in 2016.
Analysts fear Hariri's resignation could fuel a complex and already fragile internal Lebanese situation.
"I announced my resignation from the presidency of the Lebanese government," Hariri, 47, said in a speech broadcast by Al Arabiya television. He described what he currently is doing, as he was before the assassination of his father, former Prime Minister Rafik Hariri.
Hariri began his speech with statements attacking both Iran and Lebanese Hezbollah. He said that Iran "is not a place in place, but it is infested with strife, destruction, and destruction, as evidenced by its interference in the internal affairs of the Arab countries in Lebanon, Syria, Iraq and Yemen."
Hariri said that Iran "planted among the people of one country sedition and took over the authority of the state and established a state within the state and ended up that took control of the joints and has the upper word and the final say in the affairs of Lebanon and the Lebanese."
Hariri described Hezbollah, which is part of the government, as "the Iranian arm not only in Lebanon but also in the Arab countries." "Over the past decades, Hezbollah has unfortunately managed to impose a fait accompli in Lebanon with the force of its weapon, which is alleged to be a resistance weapon, which is directed at the release of our Syrian and Yemeni brothers as well as the Lebanese.","I want to tell Iran and its followers that they are losing their interference in the affairs of the Arab nation and our nation will rise as it did in the past and cut off the hands that extend to it in bad," Hariri said in his speech to Tehran.
Hariri was appointed the prime minister in November 2016 under a political settlement that brought Hezbollah's most prominent ally Michel Aoun to power as president two and a half years after the presidential vacuum.Since he entered politics 12 years ago, Hariri has fought several political confrontations with Damascus and Hezbollah but has repeatedly had to give up these two powerful rivals.
Hariri said in his speech: "We are living in an atmosphere similar to the atmosphere that prevailed before the assassination of the martyr Rafik Hariri," adding in another surprising statement: "I touched what is woven in secret to targeting my life."
Rafic Hariri and 22 other people were killed in a massive bomb attack on his motorcade in Beirut in 2005. The international tribunal charged with examining his murder accused five Hezbollah members of involvement in the operation. The Lebanese presidency issued a statement saying that Hariri had phoned Aoun to inform him of the resignation.
The Presidency added that «President Aoun is waiting for the return of Prime Minister Hariri to Beirut to learn about the circumstances of the resignation to build on the thing required».
Hariri's resignation was a surprise both for his allies and his political opponents in Lebanon. Once approved by the President of the Republic the government becomes a caretaker government.
"Frankly, Lebanon is more than small and weak to bear the economic and political burdens of this resignation," MP Walid Jumblatt, a close associate of Hariri, wrote in a tweet on Twitter.
In 2005, Saad Hariri became a political leader after he led the anti-Syrian March 14 Forces to a major victory in parliament, helped him sympathize with him after his father's death and the popular pressure that followed him and contributed to the removal of the Syrian army from Lebanon some thirty years later Of his presence in it.
Hariri headed the government last year for the second time. It was the first time between 2009 and 2011 when he headed a government of national unity that included most of the Lebanese parties and was dropped by Hezbollah and its allies, headed by Michel Aoun, the withdrawal of their ministers from them.