Syrians in Damascus voiced concern Monday at the impact on their country of the death of Iranian president Ebrahim Raisi, as some in Syria's last main opposition bastion were celebrating.

Tehran has been a key ally for Syrian President Bashar al-Assad, and housewife Hazar Mazhar said "everybody is talking about the news, but I don't know if what happened will impact us, or what the coming days will bring."

"I'm afraid of the impact on the economy... I hope this incident doesn't affect our livelihoods," the 49-year-old said.

US President Joe Biden denied Monday that Israel's war in Gaza was genocide, as he slammed an "outrageous" request by the International Criminal Court's prosecutor for an arrest warrant for Israeli leaders.

"What's happening is not genocide," Biden told a Jewish American Heritage Month event at the White House as he discussed the conflict sparked by Hamas's October 7 attack on Israel.

Israel's hawkish right-wing Prime Minister Benjamin Netanyahu is treading increasingly thin ice after the International Criminal Court's prosecutor on Monday sought an arrest warrant for him over "war crimes" in Gaza.

The silver-haired 73-year-old, known by his nickname "Bibi", has dominated his country's politics for decades but now faces mounting isolation both at home and abroad over his handling of the war against Hamas in Gaza.

The death of Iranian President Ebrahim Raisi in a helicopter crash could lead to a period of political instability but is unlikely to change Iran's foreign policy or its role in the Middle East, analysts said on Monday.

The hardline cleric was considered a favourite to succeed supreme leader Ali Khamenei, 85, who has ultimate authority in Iran, and Raisi's death will pose a challenge to the country's authorities in ensuring the stability of the political system.

Saudi Arabia's Saudia Group will buy 105 Airbus planes, the company said on Monday, hailing it as the biggest aircraft deal in the country's history.

Saudia airline will receive 54 A321neo aircraft, while budget offshoot flyadeal will acquire 12 A320neo and 39 A321neo planes, it said in a statement.

The deal is valued at $19 billion, according to a separate statement from the Future Aviation Forum, the conference in the Saudi capital Riyadh where the deal was announced.

The prosecutor of the International Criminal Court on Monday applied for arrest warrants against Israeli Prime Minister Benjamin Netanyahu and top Hamas leaders on suspicion of war crimes and crimes against humanity.

Netanyahu rejected the landmark request "with disgust", while Foreign Minister Israel Katz slammed it as "a historical disgrace that will be remembered forever."

The United States also firmly criticised the prosecutor's move.

Iran's veteran nuclear negotiator Ali Bagheri, a harsh critic of the West, was Monday named acting foreign minister to replace the top diplomat killed in a helicopter crash along with the president.

Bagheri, 56, had served as deputy to the foreign minister of the Islamic republic, Hossein Amir-Abdollahian, who perished along with the Iranian president Ebrahim Raisi and seven others in the accident.

Bagheri is considered close to Iran's ultraconservatives and a member of the inner circle of supreme leader Ayatollah Ali Khamenei, who is the father-in-law of Bagheri's brother.

Israel and Hamas, engaged in heavy fighting in the Gaza Strip, both angrily rejected on Monday moves to arrest their leaders for war crimes made before an international court.

The International Criminal Court's prosecutor Karim Khan said he had applied for arrest warrants for top Israeli and Hamas leaders over the conflict.

Israel slammed as a "historical disgrace" the demand targeting Prime Minister Benjamin Netanyahu and Defence Minister Yoav Gallant, while the Palestinian militant group Hamas said it "strongly condemns" the move.

The death of Iranian president Ebrahim Raisi in a helicopter crash is a major blow to the Islamic republic's clerical leadership, an exiled opposition group said Monday, predicting a succession of crises.

The People's Mujahedin of Iran (MEK) and its political wing the National Council of Resistance of Iran (NCRI) have long detested Raisi, accusing him of involvement in the 1988 mass executions of thousands of their members and other dissidents when he was a young prosecutor.

The Israeli flag has flown over the Gaza side of the Rafah crossing for two weeks, but uncertainty over the future of the key aid terminal has quickly become a thorn on Israel's side.

Egypt has refused to reopen its side of the crossing as long as Israeli troops control the Palestinian side, keeping shut one of the only points through which badly needed aid was reaching Gaza.