U.S. Senators John McCain and Joseph Lieberman say Washington is watching to see whether Lebanon's future government will respect the findings of a U.N. tribunal investigating the assassination of former Lebanese Prime Minister Rafik Hariri.

The 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 now that its favored candidate, Najib Mikati, has been named Lebanon's prime minister-designate.

McCain and Lieberman were in Lebanon Tuesday to meet with Lebanese officials during the political crisis.