A planned parliament session to elect a president on Wednesday appeared increasingly unlikely as intense mediation between Lebanon's factions struggled to reach a compromise candidate. Army and police were reinforced in Beirut, fearing a volatile power vacuum. A mood of frustration and pessimism settled on this small Arab nation Tuesday as a weekend deadline for an election approached. President Emile Lahoud leaves office Friday night, and fears of turmoil - including the possible creation of two rival governments - were high if no agreement was reached on his replacement. French Foreign Minister Bernard Kouchner, who has been mediating for months, said Tuesday that a parliament session to vote on a new president, scheduled for the next day, had been postponed until Friday to give rival factions more time. Kouchner, who has been mediating for months Lebanon's worst political crisis since the 1975-90 civil war, spoke to reporters after holding talks with Cardinal Nasrallah Sfeir, the head of the influential Maronite Catholic Church. Under Lebanon's division of power, the presidency is held by a Maronite, and last week Kouchner had sought Sfeir's help in finding a figure acceptable to all sides.