Michel Aoun and Samir Geagea, who fought each other in the dying years of the 1975-90 civil war, are both candidates for the Lebanese presidency that has been vacant since Michel Suleiman's term expired a year ago.

The post is reserved for a Maronite Christian according to the country's sectarian power-sharing system.

Their meeting at Aoun's house in Rabieh north of Beirut seems unlikely to yield a breakthrough: agreement on a new president is widely seen as requiring a broader deal backed by rival regional states Iran and Saudi Arabia.

The leaders issued a joint statement calling for the election of "a strong president" accepted by the Christian community and capable of reassuring Lebanon's other sects.

The presidential vacuum is part of a wider crisis fuelled by the war in neighbouring Syria that has paralysed much of the state and triggered spasms of deadly violence.

A government formed in February 2013 with Saudi-Iranian blessing has spared Lebanon from a complete vacuum in the executive arm. But that government has struggled to take even basic decisions. Parliament barely functions.

Aoun is an ally of the powerful, Iranian-backed Shi'ite Muslim group Hezbollah, which is fighting alongside President Bashar al-Assad in Syria's civil war.

Geagea is a political ally of Sunni Muslim politician Saad al-Hariri, who is backed by Saudi Arabia.

Saudi-Iranian rivalry is fuelling conflict across the region. Saudi Arabia is one of the Gulf Arab states that support the insurgency against Assad.

Geagea said his visit was to bring together the two main Christian parties. "They are two political forces which -- if they agree -- can have a positive impact on Lebanon," he said in comments reported by the Lebanese National News Agency.

Aoun said the meeting was "a gift to Christians concerned about the situation in Lebanon. The decision is in our hands and not in the hands of any other party."