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Israeli Prime Minister Benjamin Netanyahu with U.S. Secretary of State Marco Rubio at their joint press conference during Rubio’s visit, in Jerusalem, on Monday.Nathan Howard/Reuters

Israeli Prime Minister Benjamin Netanyahu said he wouldn’t rule out further strikes on Hamas leaders “wherever they are” as the heads of Arab and Islamic states held a summit to show support for Qatar after Israel‘s attack on the Gulf state last week.

The Sept. 9 strike targeting leaders of the Palestinian militant group in Doha marked a significant escalation of Israeli military action in a region shaken by conflict since the Hamas-led Oct. 7, 2023 attacks that ignited the Gaza war.

While the assembled Arab and Muslim leaders were expressing solidarity with Qatar, U.S. Secretary of State Marco Rubio met Netanyahu and gave strong backing for Israel’s hardline stance, although Washington has expressed unease over the Qatar strike.

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Speaking alongside Netanyahu in Israel, Rubio said the only way to end the war in Gaza would be for Hamas fighters to free all hostages and surrender. While the U.S. wants a diplomatic end to the war, “we have to be prepared for the possibility that’s not going to happen,” he said.

He also called on Qatar to continue to play a constructive role in resolving the Gaza conflict.

Washington has said it was not warned in advance before Israel attacked Qatar, which houses the biggest U.S. military base in the Middle East. President Donald Trump said on Sunday Israel had to be “very, very careful.”

“They have to do something about Hamas, but Qatar has been a great ally to the United States,” Trump said.

Meanwhile, the leaders of Canada, Egypt, Jordan, Qatar, and Britain held a call chaired by French president Emmanuel Macron on Monday to discuss the crisis. Prime Minister Mark Carney in a statement expressed solidarity with Qatar and said that the strike on Doha risked escalating the conflict.

“All leaders agreed that the focus must remain on advancing peace and security, including reaching a lasting ceasefire, securing the release of all hostages and the disarmament of Hamas, and scaling up flows of life-saving assistance for Palestinian civilians,” the statement said.

Mr. Carney reiterated Canada’s intention to recognize the State of Palestine in advance of the United Nations General Assembly later in September.

Hamas has said the Israeli strike on Qatar killed five of its members, including a son of its exiled Gaza chief, but its leadership survived. Qatar says one of its security agents also died.

Qatari Emir Sheikh Tamim bin Hamad Al-Thani, addressing the emergency summit, urged “practical and decisive steps” in response to the “cowardly and treacherous” Israeli strike. He said the attack occurred as Hamas leaders were studying a U.S. ceasefire proposal.

With a broad spectrum of states attending, including Iran, Turkey and Saudi Arabia, it wasn’t immediately clear what measures might be agreed at the summit. A statement was expected to say that the Israeli attack and other “hostile acts” threaten co-existence and efforts to normalize ties in the region, according to a draft seen by Reuters.

President Masoud Pezeshkian of Iran, which backs Hamas and fought a 12-day war with Israel in June, said “no Arab or Islamic country is safe from the attacks of the Zionist regime [Israel] and we have no choice but to unite our ranks.”

President Abdel Fattah al-Sisi of Egypt, a U.S. ally which signed a peace treaty with Israel in 1979, said Israel’s actions “put obstacles in the way of any opportunities for any new peace agreements and even aborts existing ones.”

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Saudi Crown Prince Mohammed bin Salman with Qatari Emir Sheikh Tamim bin Hamad Al-Thani and GCC representatives at an emergency Arab-Islamic leaders’ summit, in Doha, on Monday.Saudi Press Agency/Reuters

Rubio will travel to Qatar after his visit to Israel. He called on Qatar to continue to play a constructive role in resolving the Gaza conflict, saying it could help reach the goals of releasing all 48 hostages still held in Gaza, disarming Hamas and building a better future for Gazans.

But his words alongside Netanyahu suggested Washington now considers a diplomatic solution unlikely and is backing Israel’s plan for a major new military operation that Netanyahu says will crush Hamas once and for all.

“As much as we may wish that there be a peaceful, diplomatic way to end it, and we’ll continue to explore and be dedicated to it, we also have to be prepared for the possibility that’s not going to happen,” said Rubio, calling Hamas “savage terrorists.”

“Hamas needs to cease to exist as an armed element that can threaten the peace and security of the region,” he said.

Opinion: Israel’s Qatar bombing didn’t kill its intended targets, but it killed hopes for a Gaza ceasefire

With Rubio at his side, Netanyahu did not rule out annexing the Israeli-occupied West Bank in response to moves by some countries to recognize a Palestinian state at the UN General Assembly later this month. France and Britain are among the countries that have said they will do so.

Asked if Israel was considering extending its sovereignty to the West Bank, Netanyahu said: “A future step is a future step. We don’t need to expose it ahead of time.”

“It’s clear that taking unilateral actions against us simply invites unilateral actions on our part,” he said.

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Palestinians inspect the damage at the site of Israeli strikes that destroyed Al-Jundi al-Majhoul residential tower on Sunday, in Gaza City.Dawoud Abu Alkas/Reuters

Rubio on Monday visited a contentious archaeological site beneath Jerusalem, giving U.S. backing to a Jewish settler-led project that critics say undermines prospects for a future Palestinian state.

The City of David archeological park sits in the shadow of the elevated compound known to Jews as the Temple Mount and to Muslims as Haram al-Sharif, or the Noble Sanctuary, a flashpoint that has triggered outbreaks of violence over the decades and remains at the heart of the Israeli-Palestinian conflict.

The global heritage body UNESCO opposed construction of the park in the Palestinian neighborhood of Silwan, outside of what most of the world recognizes as Israel’s territory.

Rubio said he would be inaugurating a site attached to the park known as Pilgrim’s Road, believed to have been traversed by visitors to Judaism’s Second Temple around 2,000 years ago.

“It’s one of the most important archaeological sites in the world,” Rubio said before departing Washington on Saturday. “I understand people want to involve politics in it. I understand everything in this region is political to some extent. But at the end of the day, it’s an extraordinary archaeological site.”

Residents and Israeli advocacy groups say the excavations under Silwan have been conducted beneath Palestinian homes without consulting residents and do not meet the standards of professional archaeology.

Netanyahu’s office did not respond to a request for comment.

While diplomacy was unfolding in Jerusalem and Doha, Israeli forces were continuing their assault on Gaza City, where they killed at least 16 Palestinians in strikes on two homes and on a tent housing a displaced family, local health authorities said.

The army also hit and destroyed a 16-floor building in the west of the city, believed to be the tallest in the Gaza Strip, about an hour after warning displaced families sheltering inside and nearby to leave. It said the building was being used to hide “terrorist infrastructure.”

The war in Gaza was triggered by a rampage into southern Israel by Hamas militants who killed around 1,200 people and captured 251 hostages, according to Israeli tallies. Israel responded with an assault that has killed more than 64,000 people, according to Palestinian health authorities.