(Adds Assad-Abdullah meeting, paragraphs 6-7)
By Nadim Ladki
BEIRUT, Nov 18 (Reuters) - Diplomats intensified their efforts on Sunday to get rival Lebanese leaders to agree on a successor to the president whose term ends this week, a step vital to defusing a prolonged crisis.
Lebanon faces the prospect of two parallel governments and maybe bloodshed if parliament's Western-backed majority and the Hezbollah-led opposition fail to elect on Wednesday a successor to pro-Syrian President Emile Lahoud, whose term ends on Friday.
The deadlock, the climax of a year-old political crisis that has paralysed the country, has prompted international efforts led by France to nudge Lebanese leaders towards agreement.
Lebanese sources said French Foreign Minister Bernard Kouchner would return to Beirut on Sunday night to resume his efforts, less than a week after his last visit. He is due to hold talks with feuding leaders on Monday.
U.S. Secretary of State Condoleezza Rice called Prime Minister Fouad Siniora, parliament speaker Nabih Berri and other leaders to discuss developments, the official National News Agency reported.
In Damascus, President Bashar al-Assad discussed the Lebanese crisis with Jordan's King Abdullah. The pro-U.S. monarch, on a rare visit to Syria, has good relations with anti-Syrian Lebanese majority leader Saad al-Hariri.
A joint communique said "the two leaders affirmed the need to reach a compromise solution that preserves Lebanon's stability" and results in the election of a new president before Lahoud's term expires.
Hariri and Berri discussed on Saturday a list of candidates presented to them by Maronite Patriarch Nasrallah Sfeir.
"The atmosphere of discussions was positive and boosted the chances of consensus on the presidency," a joint statement said.
But political sources said the two did not reach agreement and would intensify their meetings in the next few days.
The majority coalition has said it will elect a president on its own if there is no deal, while the opposition have threatened to set up a second government.
The political conflict is Lebanon's worst internal crisis since the 1975-1990 civil war.
At former colonial power France's prodding, the head of the Maronite church had given a list of six candidates to Hariri and Berri to choose a new president from. The president must be a Maronite in line with Lebanon's sectarian power-sharing system.
Political sources say the list includes MP Boutros Harb and former MP Nassib Lahoud from the governing coalition and the opposition's Christian leader Michel Aoun.
But the consensus figure is expected to be one of three moderates Sfeir named -- parliamentarian Robert Ghanem, former central bank governor Michel Khoury and ex-minister Michel Edde.
Italian Foreign Minister Massimo D'Alema visited Beirut on Saturday and warned that "everything could still go wrong".
The candidate will be Lebanon's first new president since Syria pulled its troops out of Lebanon in 2005. Damascus controlled Lebanese politics until the withdrawal. (Editing by Tim Pearce)