Saudi Arabia condemned on Friday the attack against a convoy of the United Nations Interim Force in Lebanon (UNIFIL).
The Foreign Ministry called for an immediate and transparent probe into the attack that left an Irish soldier dead.
It stressed the Kingdom’s rejection of all forms of violence, underling its full support to UNIFIL.
It offered its condolences to the people and government of Ireland, wishing the wounded a speedy recovery.
The peacekeeper's convoy came under fire late Wednesday near the southern village of Al-Aqbiya, the Irish military said, wounding three other members of the UN force.
Lebanon's caretaker Prime Minister Najib Mikati and army chief Joseph Aoun visited on Friday the UNIFIL headquarters in the border town of Naqura, denouncing the attack that claimed private Sean Rooney's life.
UNIFIL spokesman Andrea Tenenti called it "a very serious incident" and told reporters it was "important" for the Lebanese authorities to bring the perpetrators to justice.
It is the first death of a UNIFIL member in a violent incident in Lebanon since January 2015, when a Spanish peacekeeper was killed during retaliatory Israeli fire.
UNIFIL was set up in 1978 to monitor the withdrawal of Israeli forces after they invaded Lebanon in reprisal for a Palestinian attack.
Now with nearly 10,000 troops, the UN force acts as a buffer between Israel and Lebanon, which remain technically at war.
Israel withdrew from south Lebanon in 2000 but fought a devastating 2006 war with the Iran-backed movement Hezbollah and its allies.
UNIFIL was beefed up to oversee the ceasefire that ended that conflict.