The resignation of Prime Minister Saad Hariri in Lebanon on Saturday changes the regional balance of power.

The Sunni politician enjoys the support of Saudi Arabia.

On Friday, Hariri met with Iranian diplomat Ali Akbar Valayati, before flying to Riyadh on Saturday. Hours later, from the Saudi capital, he resigned.

The move ends a modus vivendi with Hezbollah that is the Iran-backed political movement with a military apparatus that is far stronger than that of the Lebanese state.

Saad Hariri’s father, Rafik, was assassinated in 2005, with the subsequent investigation implicating the regime of Syrian President Bashar al-Assad and Hezbollah. More assassinations ensued, with the conflict acqu\iring international dimensions when Israel and Hezbollah fought an all-out war in 2006.

The collapse of power-sharing arrangements between the Shiite Hezbollah movement backed by Tehran and the Sunni-Hariri coalition backed by Riyadh Saudi-could have broader implications for the region.

The collapse of the Lebanese government means that Harriri considers Hezbollah as simply an illegal militia, which could pave the way for a combined attack by Israel and Saudi Arabia. In this case, Iran is likely to support Hezbollah.

Lebanon’s civil war (1975-1990) involved a war by proxy between all regional powers, who are also involved in the Syrian conflict. Over the last few years, Lebanon has received over 1,2 million Syrian refugees and has seen its infrastructure, trade, and tourism suffer, contributing to a mounting public debt.