The Syrian and Saudi leaders have called on Lebanon's rival factions to avoid turning to violence amid mounting political tensions in the country.
The call came after unprecedented talks in Beirut between Saudi King Abdullah, Syrian President Bashar al-Assad and Lebanese President Michel Suleiman.
They called on Lebanese to resolve issues through "legal institutions".
The trip marks progress in relations between Saudi Arabia and Syria - two of the region's most influential powers.
The two countries only exchanged embassies for the first time last year, and entente between them is seen as crucial to stability in Lebanon.
"The leaders stressed the importance of stability... the commitment (of the Lebanese) not to resort to violence and the need to place the country's interests above all sectarian interests," said a statement issued by the Lebanese presidency after talks between the three leaders.
Conflict looming?
The visit is Mr Assad's first to Lebanon since Syria was forced to withdraw its troops after the 2005 killing of former PM Rafik Hariri.
Both he and the Saudi leader are worried conflict could break out if, as rumoured, a UN tribunal indicts members of the Iranian-backed Hezbollah movement over the Hariri killing.
On Thursday, Mr Assad and King Abdullah pledged to work together to help stabilise Lebanon.
Hezbollah is Syria's main ally in Lebanon, while the Saudis are deeply involved with the country's Sunni community and current Prime Minister Saad Hariri, son of the murdered ex-PM.
Mr Assad and King Abdullah are thought to have been instrumental in ending the five months of deadlock which preceded the formation of Lebanon's unity government - which includes Hezbollah - last November.
'Major stability'
Lebanon's relations with Syria have been complicated since the Hariri assassination, the huge anti-Syrian demonstrations that followed, and the end of the 29-year Syrian military presence - all in 2005.
But things have improved since then, analysts say. Saad Hariri has visited Damascus twice as prime minister for talks with President Assad, setting aside his accusations that Syria was behind his father's death.
Mr Assad's visit carries that normalisation a step further.
Tensions have risen in the past week, however, with Hezbollah leader Sheikh Hassan Nasrallah reacting angrily to persistent reports that the Hariri tribunal may indict several members of the Shia Islamist group.
He made clear that he would not accept such a scenario, accusing the tribunal of being politicised and part of an "Israeli project".
Should it indeed happen there are fears of sectarian violence between Shias and Hariri's Sunni community, as happened in 2008, says the BBC's Jim Muir in Beirut.
