Lebanon’s Prime Minister Saad al-Hariri resigned on Saturday, saying he believed there was an assassination plot against him and accusing Iran and its Lebanese ally Hezbollah of sowing strife in the Arab world, Reuters reported.

Al-Hariri’s resignation came as a big surprise to Beirut’s political establishment and has plunged Lebanon into a new political crisis.

This move has reportedly thrust Lebanon into the front line of a regional competition between Sunni Saudi Arabia and Shi‘ite Iran that has also buffeted Syria, Iraq, Yemen and Bahrain. A Saudi government minister said Hariri was in Riyadh to ensure his safety.

Hariri, who is closely allied with Saudi Arabia, alleged in a broadcast from an undisclosed location that Hezbollah was “directing weapons” at Yemenis, Syrians and Lebanese, Reuters reported.

In comments directed at Iran, he said the Arab world would “cut off the hands that wickedly extend to it”.

Hariri’s coalition, which took office last year, grouped nearly all of Lebanon’s main parties, including Hezbollah. It took office in a political deal that made Michel Aoun, a Hezbollah ally, president, and was seen as a victory for Iran.

Reuters reported that the resignation risks exacerbating sectarian tensions between Sunni and Shi‘ite Muslims and returning Lebanon to paralysis in government.

Iran’s Foreign Ministry said Hariri’s departure was a plot to “create tension in Lebanon and the region”.

“Hariri’s resignation was done with planning by Donald Trump, the president of America, and Mohammed bin Salman, the crown prince of Saudi Arabia,” said Hussein Sheikh al-Islam, adviser to Iran’s supreme leader.

Sabhan, the Saudi minister, echoed the language of the Lebanese politician saying in a tweet: “The hands of treachery and aggression must be cut off.”

Reuters reported that Israeli politicians also used Hariri’s resignation to criticize Iranian influence in Lebanon. “His words are a wake-up call to the international community to take action against Iranian aggression,” Prime Minister Benjamin Netanyahu said.