The UN Security Council has called an emergency meeting from 2100 GMT on Wednesday to discuss the flare-up of violence on the Israeli-Lebanon border, diplomats told AFP.
France requested the urgent talks in the 15-member council after two Israeli soldiers and a Spanish UN peacekeeper died in the exchange of fire between Israeli forces and Hezbollah terrorists.
The violence raised fears of another all-out conflict between the two countries, who fought a month-long war in 2006, in a region already wracked by fighting with Islamists in Syria and Iraq.
Tension in the area has been building, especially after an Israeli air strike on the Syrian sector of the Golan Heights killed six Hezbollah terrorists and an Iranian general on January 18.
Israel's Ambassador to the United Nations told the Security Council in a letter that Israel will take all necessary measures to defend itself in
response to the Hezbollah attack.
"Israel will not stand by as Hezbollah targets Israelis," wrote Ron Prosor in the letter also sent to Secretary General Ban Ki-moon.
The Israeli envoy demanded that the council condemn Hezbollah and take steps to press Lebanon to disarm the Islamist militants as outlined in UN resolutions.
The clashes began when Hezbollah fired an estimated 5-6 anti-tank missiles at a military convoy in Israel, prompting Israel to respond with
air and ground strikes.
The 10,000-strong UNIFIL mission said it had observed six rockets fired towards Israel from southern Lebanon and that Israeli forces "returned artillery fire in the same general area".
The council will be meeting behind closed doors and hear a report from a senior peacekeeping official overseeing UNIFIL operations.