Suleiman Franjieh.

BEIRUT — Saudi Arabia lent its backing on Thursday to a power-sharing plan that would make a family friend of Syria’s Bashar al-Assad president of Lebanon, saying it hoped it would happen within weeks.

The proposal tabled by Sunni politician Saad al-Hariri would see him return to Lebanon as prime minister and make Maronite Christian politician Suleiman Franjieh president. Hariri is backed by Saudi Arabia.

Franjieh is a member of parliament and the grandson of a former president.

The plan could revive government institutions paralyzed by political rivalries that have been exacerbated by the war in neighboring Syria. Lebanon has been without a president for 18 months.

“God willing we will see … this vacuum filled thanks to good efforts in Lebanon” around the end of this year, said Ali Awad Asiri, the Saudi ambassador to Lebanon.

“We bless this initiative and we are keen to see this presidential vacuum filled,” he said. He was speaking in a televised news conference after meeting officials of one of Lebanon’s main Christian parties, the Kataeb.

The comments follow similar encouragement from Saudi’s arch-rival Iran. Visiting Beirut this week, Ali Akbar Velayati, a top adviser to Iran’s supreme leader, said he hoped to see the election of a president “in the immediate future.”

Saudi Arabia backs the Hariri-led March 14 coalition which was forged a decade ago out of opposition to Syria’s influence in Lebanon, while Iran backs Hezbollah, which dominates the rival March 8 alliance.

But a deal could yet be undone by local rivalries.

The toughest challenge is winning over other Maronite politicians who are seeking the presidency, notably Michel Aoun, an ally of Hezbollah, and Samir Geagea, still officially March 14’s candidate for president.

Speaking in France after a meeting with President Francois Hollande, Hariri said there was “great hope” of ending the paralysis that arose from the failure of rival politicians to agree on who should fill the presidency.