French President Emmanuel Macron has said he will stress the importance of stability in Lebanon as he began an unscheduled visit to Saudi Arabia.
This comes after Lebanese PM Saad Hariri resigned on Saturday while in Riyadh, saying he feared for his life.
This prompted suspicions that Mr Hariri was pressured by the Saudis to resign.
Mr Macron also said he would discuss the crisis in Yemen with Saudi leaders, after the Saudi-led coalition shut all aid routes to the war-torn nation.
The blockade was imposed on Monday after a missile was fired from Yemen at Riyadh. The missile was reportedly intercepted near the Saudi capital.
Saudi Arabia has blamed the Iranian-backed Lebanese militant group Hezbollah for the attack.