Lebanese lawmaker Najib Mikati was tipped to be designated as the eastern Mediterranean country's new prime minister after securing 68 out of 128 parliamentary, votes beating his contender caretaker Prime Minister Saad Hariri who gathered 60 votes.

The imminent designation of Mikati as head of Lebanon's new cabinet was announced as riots in support of Hariri erupted all across the country, in the capital Beirut and the northern coastal city of Tripoli.

Mikati's expected designation comes amid heightened tension among rival Lebanese groups over the Special Tribunal for Lebanon (STL), which is probing the assassination of the caretaker prime minister's father, Sunni statesman Rafic Hariri. The UN-backed court is widely expected to point the finger at Shiite armed group Hezbollah.

Future Movement MP Ahmad Fatfat said street protests meant to send a clear message to Hezbollah that the Shiite party will not be allowed to name the country's prime minister, reserved to a Sunni by convention.

Hezbollah and its allies in the March 8 coalition, as well as MPs from Druze leader Walid Jumblatt's parliamentary bloc, voted in favor of Mikati, who presents himself as a consensus candidate.