Countries of the United Nations Security Council (UNSC) have condemned the assassination of Hamas’s political chief Ismail Haniyeh in Iran and called for stepped-up diplomatic efforts to prevent an all-out war in the Middle East.

The UNSC’s emergency meeting on Wednesday came as Iran and Hamas – the Palestinian group that governs the war-torn Gaza Strip – blamed Israel for Haniyeh’s death and pledged to seek revenge. Israel has not admitted responsibility for the attack in Tehran.

At the UNSC meeting, Palestine said the global community must stop Israel from dragging the Middle East into the "abyss”, while China, Russia and Algeria condemned Haniyeh’s assassination. The United States, United Kingdom and France raised what they said was Iranian support for destabilising actors in the region, while Japan said it feared an all-out war in the Middle East.

"Israel has been the oppressor, tormentor and murderer of Palestinians for decades, and it is the longstanding destabiliser of our region,” said Feda Abdelhady Nasser, the deputy permanent observer of the State of Palestine to the UN. "It must be stopped,” she said, while also calling for accountability for the killing of Haniyeh as well as the "murder and injury of over 130,000 Palestinian children, women and men across these past 300 days of horror and hell in Gaza”.

Iran’s UN Ambassador Amir Saeid Iravani said Tehran has consistently exercised maximum restraint but reserved its right to respond decisively to Haniyeh’s assassination.

He called on the UNSC to condemn Israel and punish it with sanctions. (Agencies)