The Syrian Foreign Ministry condemned the assassination of the Hamas leader, warning of the risk of escalation spreading to the entire region. The Houthi movement in Yemen declared the assassination a criminal act, a blatant violation of the law and moral values.

Turkish President Recep Tayyip Erdogan condemned the assassination of Ismail Haniyeh, and Iranian President Masoud Pezeshkian warned of retaliation for the assassination. Egypt's Foreign Ministry called for the situation to not escalate out of control.

Russia called it “an unacceptable political assassination”. It will lead to a further escalation of tensions, Russian Deputy Minister of Foreign Affairs Mikhail Bogdanov told the state-run RIA Novosti news agency. “The most difficult period of confrontations is beginning in the region,” Konstantin Kosachev, the vice-president of Russia's Federation Council (Senate) wrote on Telegram.

Israel has not claimed responsibility for Haniyeh’s killing but its Foreign Ministry has instructed Israeli diplomatic missions around the world to tighten security measures against possible retaliatory attacks.

Haniyeh’s funeral will be held in Doha, the capital of Qatar, on Friday. Doha is where Mr. Haniyeh has lived since 2019.  

At Iran's request the UN Security Council held an emergency meeting Wednesday to discuss the dangerous escalation in the Middle East. UNSC members affirmed the urgency of cooling down the situation, achieving a ceasefire, and deploying diplomatic efforts to prevent the conflict from escalating throughout the region.

US Secretary of State Antony Blinken said on Wednesday that the United States was not involved in the assassination of Haniyeh, and reiterated the importance of a ceasefire in Gaza.

The European Union on Wednesday said it had begun paying 430 million USD in emergency funding to the Palestinian Authority to help address its "critical" budget problems.