BEIRUT, Lebanon - Parliament yesterday again failed to meet on electing a new president, as Lebanon's factions deadlocked over a tangle of issues, including an amendment to the constitution and the shape of a future government.

Politicians have been moving toward a deal to name the army commander as president, a compromise to end the dangerous power vacuum since President Emile Lahoud stepped down Nov. 23 with no successor.

But installing Gen. Michel Suleiman as president requires an amendment to the constitution, which currently bars a sitting army commander from holding the post. The feuding factions cannot agree on how to change the constitution.

In a perhaps even tougher obstacle, Christian opposition leader and presidential hopeful Michel Aoun is demanding a "political understanding" on a future cabinet to replace that of Western-backed Prime Minister Fuad Saniora before he will allow a vote on Suleiman.

The opposition demands 45 percent of the seats in the next cabinet and a "compromise prime minister" to head the government, said Ibrahim Kenaan, a member of Aoun's 23-member mainly Christian bloc. Government supporters were refusing to discuss the demands, he said Thursday.

The presidency is the latest crisis in Lebanon's yearlong political turmoil, caused by the power struggle between anti-Syrian politicians who hold a slim majority in parliament and back Saniora's government and the opposition, which is led by Iran's and Syria's ally Hezbollah.

Despite mediation by French Foreign Minister Bernard Kouchner and prodding from U.N. Secretary-General Ban Ki-moon, the factions were still tied up in political wrangling.

Parliament had been due to convene yesterday to begin the process of amending the constitution and voting on a president, who is chosen by Lebanon's 128-member legislature.

But when the body failed to reach the needed two-thirds quorum, Parliament Speaker Nabih Berri put off the session until Tuesday.

Parliament has failed several times since September to meet on the presidential issue because the opposition is boycotting the sessions, preventing quorum, until a deal is reached.