Nabih Berri says a consensus candidate could break the deadlock over the presidency.
“We do not fear terrorism and this will not break our will. It will only reinforce our determination to prevent the terrorists from succeeding,” Ghazi Aridi, Lebanon’s information minister, said.
Ghanem’s assassination came as Lebanese deputies were beginning preparations to elect a successor to Emile Lahoud, Lebanon’s president and a pro-Syrian figure.
The United Nations and several foreign governments have condemned the car bombing.
“The security council reiterates its condemnation of all targeted assassinations of Lebanese leaders … and demands an immediate end of the use of intimidation and violence against the representatives of the Lebanese people and institutions,” the UN Security Council said in a non-binding statement which was approved by all 15 members.
Members of the March 14 bloc have accused Syria of being behind a string of political assassinations and attacks since October 2004.
The March 14 bloc of parties is widely considered to be against any Syrian interference in Lebanese affairs.
Zeina Khodr, Al Jazeera’s correspondent in Beirut, said the March 14 bloc was preparing to issue a statement blaming Syria.
The Lebanese government announced a period of mourning in the aftermath of Ghanem’s murder.
The education ministry said all schools and universities will remain closed until Friday.
Fearing for his life, Ghanem had fled into exile following the assassination in June of Walid Eido, another anti-Syrian MP from the March 14 bloc, and only returned to Lebanon on Sunday.
Ghanem’s death has reduced the bloc’s majority in parliament to 68 members out of the 127-member house, with numbers set to play a key role in the presidential vote.
“This is an attack aimed at sabotaging all efforts to reach a solution to the current political crisis,” Butros Harb, an MP and presidential candidate, said.
“You cannot separate this killing from the presidential election.”