(Corrects spelling of parliament speaker's first name to Nabih in paragraph 3)
* Syrian conflict fuelling political rivalries in Lebanon
* Country struggling with violence and economic decline
* Parliament postpones vote on president to July 23
BEIRUT, July 2 (Reuters) - Lebanese lawmakers failed to elect a president on Wednesday, for the eighth time, to succeed Michel Suleiman whose term ended in May, prolonging a political vacuum as the country struggles with violence, economic decline and an influx of Syrian refugees.
The civil war in neighbouring Syria has aggravated long-standing rivalries in Lebanon, where political power is divided among religious communities - the presidency goes to a Maronite Christian, the parliament speaker is a Shi'ite Muslim and the prime minister a Sunni.
Parliament speaker Nabih Berri said he would postpone a vote for a new president until July 23 because not enough parliamentarians turned up to the assembly on Wednesday. Political groups have boycotted sessions in recent weeks and blamed each other for the deadlock.
Some of Lebanon's deepest political divisions come over the handling of the Syrian crisis, which has driven around 1 million refugees into Lebanon.
Politicians from the March 8 coalition, which includes Shi'ite Muslim group Hezbollah, support Syrian President Bashar al-Assad. The rival March 14 coalition backs Assad's opponents.
The two blocs were formed after the assassination of former Prime Minister Rafik al-Hariri in 2005. March 14 accused Syria and Hezbollah of responsibility, a charge they deny.
Regional powerbrokers Saudi Arabia and Iran support March 14 and March 8 respectively, complicating efforts to agree on a presidential candidate.
The deadlock comes at a time of worsening security. Three suicide bomb attacks late last month targeted Beirut and a checkpoint on the road to Syria. The Syrian crisis and the political stalemate have also hit the Lebanese economy, prompting the central bank to introduce stimulus packages.
Prime Minister Tammam Salam's government has taken over some presidential duties until a new president is chosen.
The presidency was once the leading political office in Lebanon, but that power was eroded under the agreement which ended the country's civil war, handing greater influence to the government and prime minister.
Michel Aoun, a Christian leader allied with Hezbollah, has suggested that the constitution be amended to allow voters rather than members of parliament to elect the president.
Under Aoun's proposal, Christians would vote in a first round and the top two candidates would run in an election open to all voters. Observers say any such changes are unlikely given the uncompromising political atmosphere.
Samir Gagea, leader of the anti-Assad group Lebanese Forces, told a news conference: "The goal of putting forward a constitutional amendment is to divert attention from the presidential election." (Reporting by Laila Bassam, Writing by Sylvia Westall; Editing by Janet Lawrence)