Former Lebanese prime minister Saad al-Hariri said on Monday he was committed to backing his rival Suleiman Franjieh for the presidency, indicating an almost two-year deadlock over the job will not be resolved soon.

There are two main candidates - Marada movement head Franjieh and former general Michel Aoun - for president, a post reserved for a Maronite Christian. Parliament has met at least 35 times without being able to agree on who should get the job.

Hariri, the Sunni Muslim leader of the Future Movement party, returned to Beirut on Sunday to mark the 11th anniversary of the assassination of his father, former prime minister Rafik al-Hariri.

He has been holding consultations with Lebanese politicians from his March 14 bloc and others.

"We have a commitment and our commitment to Suleiman (Franjieh) is clear," he said after meeting his ally Sami Gemayel, head of the Kataeb Christian party.

It was only Hariri's third visit to the country since the Hezbollah-dominated March 8 alliance toppled his government in 2011 and he left for exile in Saudi Arabia and France.

Lebanon has been without a president for nearly two years and rival political blocs, backed respectively by rival regional powers Saudi Arabia and Iran, have failed to reach an agreement on who should fill the vacuum.

On Sunday, Hariri publicly confirmed for the first time that he put forward a proposal late last year for Franjieh, an ally of Hezbollah and friend of Syrian President Bashar al-Assad, to fill the post of president.

Some of Hariri's March 14 allies disapproved of Franjieh being nominated. Last month, Christian politician Samir Geagea, a Hariri ally, declared his support for the 80-year-old Aoun. Hezbollah also says it is backing Aoun.

Hezbollah, which is backed by Iran, is fighting in Syria alongside the Syrian army against insurgents who have received backing from Saudi Arabia, Turkey and other states.