A Lebanese Christian leader has pulled out from the presidential race and endorsed the candidacy of his rival, Michel Aoun.

The withdrawal by Samir Geagea at a press conference Monday is the latest political maneuvering aimed at resolving Lebanon's 20-month political deadlock.

Geagea and Aoun, both presidential candidates, were angered along with other Christian politicians late last year when former Lebanese Prime Minister Saad Hariri, a Sunni, nominated politician Sleiman Frangieh for president without consulting them.

According to the country's power-sharing system, the president must be a Christian, the prime minister a Sunni Muslim and the parliament speaker a Shiite Muslim.

It was not clear whether Aoun, an 80-year-old ex-army commander, can garner enough parliament votes to become president.

The country's top post has been vacant since May 2014.