Iran’s foreign minister warned Friday that if Israel’s attacks on the Gaza Strip don’t stop immediately, the violence could spread to other parts of the Middle East.

Hossein Amirabdollahian is on a tour that took him to Baghdad before Beirut, and later in the day he is scheduled to travel to the Syrian capital, Damascus. Iran heads the so-called “axis of resistance” that includes powerful militant groups in the region, such as Hezbollah in Lebanon and the Popular Mobilization Forces in Iraq. Follow Israel-Hamas war LIVE updates here.

Amirabdollahian spoke to reporters in Beirut after a meeting with his Lebanese counterpart, during which the two officials called for an end to Israel’s attacks on Gaza. He also met with Hezbollah leader Hassan Nasrallah, as well as caretaker Prime Minister Najib Mikati and the speaker of parliament.

There have been concerns that the war could spread to Lebanon’s border where Hezbollah fighters have been on alert following Hamas’ attack on southern Israel on Saturday that left hundreds of people dead.

On Thursday, Israel’s military struck two of Syria’s main international airports, in Damascus and Aleppo, putting them out of service. Flights were diverted to an airport in the coastal province of Latakia. The strikes came after shells were fired from Syria into the Israeli-occupied Golan Heights.

Sporadic acts of violence along the Lebanon-Israel border over the past days left three Hezbollah fighters dead on Monday. Israel’s military said one Israeli soldier was killed in an anti-tank missile attack on Wednesday.

US President Joe Biden has warned other players in the Middle East not to join the conflict, sending American warships to the region and vowing full support for Israel.

“What is funny is that at a time when America is calling on parties for self restraint, it is allowing the criminals in the fake Zionist entity to kill women, children and civilians in Gaza,” Amirabdollahian said.

He warned that “if these organized war crimes that are committed by the Zionist entity don’t stop immediately, then we can imagine any possibility.” He did not elaborate but it was an apparent hint that Iran-backed groups could join the war.

Senior Hamas official Ali Barakeh told The Associated Press this week in Beirut that allies like Iran and the Lebanese Hezbollah “will join the battle if Gaza is subjected to a war of annihilation.”

Amirabdollahian said: “America cannot send weapons and bombs to kill women, children and civilians in Gaza and at the same time calls on all sides for self-restraint.”

Amirabdollahian called on the foreign ministers and the leader of the Organization of Islamic Cooperation, a grouping of 57 countries with important Muslim populations, to hold a meeting to discuss the situation in Gaza.

After meeting Mikati, Amirabdollahian said the aim of his visit to Beirut is to preserve security in Lebanon amid regional tensions. “What is important for us is security in Lebanon and how to preserve calm,” Amirabdollahian said.

He added that what Hamas did over the weekend was in response to the policies of Israel’s Prime Minister Benjamin Netanyahu.