Lebanese Christian politician Samir Geagea backed his rival Michel Aoun for the presidency on Monday, reshaping Lebanese politics in an apparent break with his Saudi-backed allies which aligns him with a civil war era enemy supported by Hezbollah.
The surprise announcement edges 80-year-old Aoun closer to the presidency, vacant for 20 months, and marks a rare show of unity in a Christian community riven by divisions for decades.
But he must still secure wider backing to secure the position reserved for a Maronite Christian in Lebanon's sectarian political system.
In the Lebanese political system, the presidential seat is reserved for Maronite Christian candidates while Prime Minister seat is reserved for Sunnis, and government speaker post is reserved for Shiite politicians.
Geagea and Aoun, who fought each other in the 1975-90 civil war, have been on opposite sides of Lebanon's political divide since Syrian forces withdrew from Lebanon in 2005.
Aoun is part of the March 8 alliance dominated by the Iranian-backed Shiite group Hezbollah. Geagea is part of the March 14 alliance led by Sunni politician Saad al-Hariri, who is in turn backed by Saudi Arabia.
Sitting with Aoun at a news conference, Geagea said the move was intended to rescue Lebanon from political crisis. The government barely functions, paralysed by rivalries exacerbated by regional conflict.
Geagea said the step "carried hope of getting out of the situation we are in, to a situation that is more secure, more stable - a normal life." Lebanon was on the verge of the abyss, requiring "an unusual rescue operation, regardless of the price", said Geagea, who himself covets the presidency.
The rapprochement may kill off a proposal by Hariri that nominated another Maronite, Suleiman Franjieh, for the presidency in a power-sharing proposal that would have made him prime minister.
Both Geagea and Aoun opposed that initiative which was backed by both Iran and Saudi Arabia.
Suleiman Franjieh was born in October 1965, and is the grandson of the late Lebanese President Suleiman Franjieh, who he is named after.
Geagea had been the official presidential candidate of the March 14 alliance until Hariri tabled Franjieh - part of March 8 - as an alternative. Though Franjieh has close ties to Hezbollah, the group has stuck by Aoun.
Drafted by Sunni politician Saad Hariri who enjoys Saudi support, the plan was initially welcomed by many parties although it pushes forward a presidential candidate, Suleiman Franjieh, who enjoys a close friendship with Syrian regime president Bashar al Assad.
Saudi Arabia backs Hariri’s plan, although the kingdom is a stringent critic or the brutal Assad regime. The plan sees Hariri reprising his past post of prime minister in Franjieh government.
Geagea called on his March 14 allies to back Aoun after reading a joint declaration that called for a new parliamentary election law and an "independent foreign policy" while declaring Israel an enemy - an important consideration for Hezbollah.
Aoun said the "black page" of the past was over and "must be burnt". "We must leave the past in order to build a future," he said in the conference at Geagea's home in Maarab in mountains overlooking the Christian town of Jounieh.
'March 14' to break up?
The Lebanese parliament elects the president, and a two-thirds quorum is required for the vote to go ahead. Even with Geagea's backing, Aoun and his existing allies do not have enough sway to secure his election.
More importantly, Parliament Speaker Nabih Berri, a powerful Shiite politician who heads the Amal Movement and is also part of March 8, has said he will not call parliament to elect a president unless all the main sectarian parties attend.
That means Aoun must win Sunni backing in addition to the strong Shiite support he enjoys from Hezbollah.
An MP in Hariri's Future Movement, Mohamed Kabara, signalled discord over the declaration, saying "partnership is not about arm twisting, or imposition."
Nabil Boumonsef, a commentator in the an-Nahar newspaper said it marked a big change in the Christian and Lebanese political landscapes. "The biggest result will be the break up of March 14 as a result of this landscape," he said.
The March 14 alliance was forged in 2005 from groups opposed to Syrian influence over Lebanon, and enjoyed great support from the US administration of President George W. Bush, in addition to Hariri's backers in Saudi Arabia.
Tensions between March 8 and March 14, particularly over the question of Hezbollah's arsenal, spilled into a brief civil war in 2008. Hezbollah has since deployed fighters to Syria where it is battling alongside Bashar al Assad forces.
Why Lebanon needs a president
Lebanon suffers from a political deadlock caused by being a leaderless country strategically placed between Israel and war torn Syria.
With a collectively agreed upon president life can be brought back to many paralysed government institutions, stalled as a result of political divisions and a rapidly growing garbage disposal problem that crippled Beirut last summer.
The shutting down in July of the capital's main landfill site Naameh, which had the capacity to receive only 2 million tonnes of waste but had instead taken in over 15 million tonnes, caused huge amounts of rubbish to mount up in the streets across Beirut.
The pile up triggered anti-government protests and has raised health concerns. Worries have also been growing over contamination should the crisis linger into the upcoming rainy season.
The protests organised by the "You Stink" movement brought thousands from all walks of life onto the streets of Beirut demanding the government solve the problem immediately.