Iran has described the "excuses" put forward to justify Israel's attack Friday on a Beirut southern suburb as "completely unjustified and baseless."

Foreign ministry spokesman Esmaeil Baqaei called for "decisive measures" from the international community to address the "lawlessness" of Israel's continual use of military force from Gaza to Syria and Lebanon.

An already fragile ceasefire between Israel and Hezbollah appeared to be on shaky ground Friday after rockets fired from Lebanon into northern Israel triggered Israeli airstrikes in the southern suburbs of Beirut.

The rocket launch from Lebanon was the second in a week, after a lull since December. In both cases, Hezbollah denied being behind the attacks.

The defense ministers of Lebanon and Syria signed an agreement in Jeddah "to address security and military threats" along their common border, the official Saudi Press Agency reported on Friday.

Lebanon must disarm Hezbollah as agreed under the terms of the November truce with Israel, the U.S. State Department said Friday, after rocket fire prompted Israel to bomb Beirut's southern suburbs for the first time since the agreement came into effect.

The United States said Friday that it slapped sanctions on a Lebanon-based “sanctions evasion network” that supports Hezbollah’s “finance team, which oversees commercial projects and oil smuggling networks that generate revenue for Hezbollah.”

Deputy U.S. Special Envoy for Middle East Morgan Ortagus said that Friday’s ceasefire violation came from Lebanon and that Israel had the right to respond.

She was speaking to Al-Arabiya TV after Israel carried out an airstrike in Beirut’s southern suburbs, the first since the end of the war, in response to two rockets that were fired from Lebanon.

Prime Minister Nawaf Salam on Friday called Israel’s strike on two buildings in the Beirut southern suburb of al-Jamous "a dangerous escalation," urging the army chief "to act quickly to... uncover those behind the irresponsible rocket fire that threatens Lebanon's stability" and arrest them.

Israeli Prime Minister Benjamin Netanyahu said the Israeli airstrike that destroyed two buildings in Dahieh earlier in the day, the first since the latest war with Hezbollah, was “another example” of Israel’s “determination.”

President Joseph Aoun said Friday that he condemns the Israeli airstrike on Beirut’s southern suburbs and any attempt to “bring back the circle of violence” to the country.

Speaking during a news conference in Paris, Aoun said the Lebanese Army is investigating who fired two rockets at north Israel in the morning and “we will not allow anyone to use Lebanon as a launching pad."

The Lebanese Army said Friday it had identified the site of a rocket launch that triggered Israeli strikes, including on Beirut's southern suburbs for the first time since a November Hezbollah-Israel ceasefire.

"The army was able to identify the rocket launch site in the Qaaqaaiyet al-Jisr area" in south Lebanon's Nabatiyeh district just north of the Litani River, an army statement said.