Qatari Emir Sheikh Tamim bin Hamad Al Thani on Monday slammed Israel for its “blatant, treacherous, and cowardly aggression”. 

He accused Israel of trying to derail Gaza ceasefire efforts with its attack on Hamas in Doha, as Arab and Muslim leaders held emergency talks Monday to discuss a unified response.

The joint Arab League and Organisation of Islamic Cooperation summit was called by Qatar to pile pressure on Israel, which has been facing mounting calls to end the war and humanitarian crisis in Gaza.

Hamas said top officials survived last week's air strike in Doha, which killed six people and triggered a wave of criticism, including a rebuke from US President Donald Trump.

Qatar has been a key mediator in talks to end the war in Gaza -- alongside Egypt and the United States -- and the Israeli strike came as Hamas officials were discussing a new US proposal.

"Whoever works diligently and systematically to assassinate the party with whom he is negotiating, intends to thwart the negotiations," the Qatari emir said in his opening remarks.

"Negotiations, for them, are merely part of the war."

The emir also said Israeli Prime Minister Benjamin Netanyahu "dreams of turning the Arab region into an Israeli sphere of influence, and this is a dangerous illusion".

A draft final statement from the summit seen by AFP warned that Israel's "brutal" aggression "threatens all that has been achieved on the path toward establishing normal relations with Israel, including existing and future agreements".

Israel and its main backer the United States have been trying to expand the Abraham Accords, which established ties with the United Arab Emirates, Bahrain and Morocco in 2020.

As the meeting opened in Doha, US Secretary of State Marco Rubio was visiting Israel in a demonstration of Washington's steadfast support.

Rubio will head to Qatar, also a staunch Washington ally, on Tuesday, a US official said.

According to the draft statement, the nearly 60-country grouping in Doha will also emphasise "the concept of collective security... as well as the necessity of aligning together to face common challenges and threats".

Crown Prince Mohammed bin Salman, Saudi Arabia's de facto ruler, was among those present, as were Iranian President Masoud Pezeshkian, Iraqi Prime Minister Mohammed Shia al-Sudani, Turkish President Recep Tayyip Erdogan and Palestinian president Mahmud Abbas.

Jordan's King Abdullah II and Pakistani Prime Minister Shehbaz Sharif also attended.

Hissein Brahim Taha, secretary-general of the Organisation of Islamic Cooperation, said the summit is an opportunity to take a “unified and firm stance against the heinous Israeli aggression”.

Ahmed Aboul Gheit, secretary-general of the Arab League, called Israel a “rogue state” and called for an end to international silence on its crimes.

Iraqi Prime Minister Mohammed Shia al-Sudani proposed a NATO-style defence pact for the community of Arab and Islamic states.

Turkish President Recep Tayyip Erdogan called for “self-sufficiency” for the region.

Separately, the United Nations Human Rights Council said it would host an urgent debate on Tuesday on Israel's air strike in Qatar.

Meanwhile, Israeli Prime Minister Benjamin Netanyahu has not ruled out further strikes on Hamas leaders following last week's attack in Qatar, saying they would not have immunity "wherever they are".

Speaking at a joint press conference with US Secretary of State Marco Rubio in Jerusalem, Netanyahu said every country had the right "to defend itself beyond its borders".

Israel's decision to target senior Hamas leaders in Qatar - a close US ally - drew international outrage and criticism from US President Donald Trump. Hamas said six people were killed but that its leaders survived.

When pressed on whether the US had any involvement in the strike, Netanyahu told journalists: "We did it on our own. Period."

The meeting between Rubio and Netanyahu comes as Arab leaders hold a summit in a show of support for Qatar. Its prime minister urged the international community to stop applying "double standards" and to punish Israel.

In response to a question from the BBC about whether Israel's strike had damaged US relations in the region, Rubio said Washington maintained "strong relationships with our Gulf allies".