The UN-backed tribunal is widely expected to accuse Hezbollah members of involvement in the 2005 killing. The Shiite militant group and its allies walked out of the previous government after then-Prime Minister Saad Hariri — the slain man's son — refused to denounce the tribunal.

Hezbollah may be in a position to block the court's work after its favored candidate, Najib Mikati, was named Lebanon's new prime minister.

Participants at a rare meeting of Sunni leaders hosted by the grand mufti Thursday warned that such a decision would have negative consequences.