Saudi King Salman bin Abdulaziz on Monday met with outgoing Lebanese Prime Minister Saad Hariri, who announced his resignation on Saturday citing Iran's "grip" on the country and threats to his life, Al Arabiya reported.

During the meeting, "they reviewed the situation in Lebanon", said the state-run agency Saudi Press Agency.

The Saudi interior minister, foreign minister and minister of state for Arab and Gulf affairs were also in attendance.

Hariri, whose resignation was broadcast from Saudi Arabia, said he was stepping down as he believed there was an assassination plot against him. He accused Iran of sowing strife in the Arab world with its Lebanese ally, Hezbollah.

The 47-year-old politician's resignation comes less than a year after his government, to which Hezbollah's political wing belongs, was formed.

"Iran has a grip on the fate of the region's countries... Hezbollah is Iran's arm not just in Lebanon but in other Arab countries too," he said.

Hassan Nasrallah, the head of Hezbollah, said on Sunday that Hariri's resignation had been "imposed" by Saudi Arabia.

"It is clear that the resignation was a Saudi decision that was imposed on Prime Minister Hariri. It was not his intention, not his wish and not his decision" to quit, Nasrallah said in a televised address.

The Hezbollah leader also questioned why Hariri gave his resignation speech from Saudi Arabia.

Lebanese President Michel Aoun, a political ally of Hezbollah, will wait to accept or reject Hariri’s resignation until he returns to Lebanon to explain his reasons, sources at the presidential palace said, delaying for now politically difficult consultations on his successor.

In Lebanon’s sectarian system the president must be a Maronite Catholic, the prime minister a Sunni and the speaker of parliament a Shia. Hariri is Lebanon’s most influential Sunni politician.

His father, Rafik al-Hariri, was prime minister after Lebanon’s 1975-1990 civil war and was assassinated in a car bombing in 2005.

Saudi media have published reports of a plot to assassinate Hariri in recent days, but all of Lebanon’s main security branches have said they have no information about such a plot.

A Saudi minister said on Saturday that Hariri’s personal security detail had "confirmed information" about the plot.

Thamer al-Sabhan said in an interview with a Lebanese TV station on Saturday that there are "threats against the prime minister and the Kingdom is keen for his security".