* Rival leaders meet for first time since May

* UN shelves plans for election next month

PALERMO, Italy — Libya's two main rival leaders met for the first time in more than five months and the prime minister backed a UN plan for an election next year, as Italy hosted a reconciliation conference a week after a vote was shelved for next month.

Prime Minister Fayez Al-Serraj, whose weak but internationally recognized government is based in western Libya, met the commander who rules most of the east, Khalifa Haftar, in Palermo, Sicily on Tuesday.

There were no announcements of major diplomatic breakthroughs, but Serraj's spokesman said on Twitter the prime minister was committed to a UN road map to hold an election in the spring after a constitutional framework is put in place.

An Italian diplomat said Haftar, for his part, had given his backing for Serraj to remain in office as prime minister until the election can be held.

"You don't change the horse until you cross the river," the diplomat quoted Haftar as saying.

Despite Haftar having said he would not participate in the conference, photos released by the Italian government showed him with Serraj and Italian Prime Minister Giuseppe Conte embracing and smiling in a three-way handshake.

The Libyan rivals were also pictured in a group photo with dignitaries including Conte, Egyptian President Abdel Fattah El-Sisi, EU Council President Donald Tusk, Russian Prime Minister Dmitry Medvedev and French Foreign Minister Jean-Yves Le Drian. However, a source in Haftar's command said he skipped the official final summit photo.

More than seven years after long-serving leader Muammar Gaddafi was toppled by Western-backed rebels with NATO air support, no central authority has asserted control over Libya and armed groups control the streets.

The United Nations has blamed a spike in violence for its decision to drop plans to hold an election next month. It still aims for a vote next year, but says Libyans should first decide what sort of election they want.

Italy, the former colonial power which has large oil and gas interests in Libya and has been working to halt people-smuggling from the Libyan coast across the Mediterranean, had called the summit in a bid to bring together Libya's competing factions.

Haftar, a former officer in Gaddafi's military who lived for years in exile in the United States, has emerged as the leader of the most powerful armed faction, having defeated militants in the east with support from Egypt and Arab states.

Serraj heads the government in the west, which has struggled to exert control beyond the capital Tripoli. Rival parliaments in the east and west also claim legitimacy as the legislature for the entire country.

Although he came to Palermo, Haftar had poured scorn on the summit, saying he was there only for bilateral meetings with regional leaders, not for the conference itself.

"I will not take part in the summit even if it takes 100 years,” he said in a television interview viewed by Reuters before it was aired. Haftar and Egypt's Sisi, who strongly supports him, both skipped the opening dinner on Monday evening. Sisi also did not attend the final summit picture.

Italy has been eager to play a high profile role in Libyan diplomacy, competing with France, which staged a conference in May, the last time Haftar and Serraj met. The May conference produced a commitment to hold the December election but that has now been indefinitely postponed.

On Monday UN Libya envoy Ghassan Salame told Reuters he hoped another attempt to hold an election would take place by June but Libyans should first hold a national conference in early 2019 to decide on the vote’s format.

France has been courting Haftar, who is supported by Egypt and the United Arab Emirates, which see his forces as a bulwark against Islamists. Italy backs Serraj and his weak Government of National Accord (GNA), and has worked with local groups in Libya to stop Europe-bound migrants from embarking by boat. — Reuters