An Israeli airstrike on Wednesday killed three sons of one of the most senior leaders of Hamas, Ismail Haniyeh, who said the strike would not weaken the group’s negotiating position or its resolve in its fight against Israel.
Mr. Haniyeh, who leads the Hamas political bureau from exile, is a longstanding leader of the group. He is also engaged in the stalled negotiations with Israel through international mediators who are seeking to broker a cease-fire and secure the release of Israeli hostages held by Hamas in the Gaza Strip.
“The enemy is delusional if it thinks that by killing my children, we will change our positions,” Mr. Haniyeh said in a statement. “We shall not give in, no matter the sacrifices.”
Mr. Haniyeh, who has long shuttled between Qatar and Turkey, said in the statement that 60 members of his extended family had been killed by Israel over time and that the strike on Wednesday had killed some grandchildren in addition to the three sons.
Hamas’s critics, including some Palestinians, have accused the organization’s leadership of living luxurious lifestyles abroad as the people in Gaza suffer dire humanitarian conditions. Mr. Haniyeh on Wednesday cast his loss in the broader context of Palestinian suffering.
“All the members of our people and the families of the residents of Gaza have paid a great price of the blood of their children,” he said. “I am one of them.”
Mr. Haniyeh did not specify his sons’ roles in Hamas but called them martyrs, saying in an statement on the group’s official Telegram account that they had remained in the Gaza Strip while he led Hamas’s political bureau from exile.
In confirming the strike on Mr. Haniyeh’s three adult sons — who it named as Amir, Mohammad and Hazem Haniyeh — the Israeli military said all three were Hamas military operatives. The strike was conducted on Eid al-Fitr, the holiday that marks the end of the holy month of Ramadan.
The killing of Mr. Haniyeh’s family members came as Israel continued to threaten to carry out an offensive in the southern city of Rafah and as both sides were considering new cease-fire proposals.
As part of those cease-fire talks, Hamas informed Israel on Wednesday that it could not locate 40 Israeli hostages in Gaza, who the Israelis had hoped would be released as part of a proposed first step in a deal, a senior Israeli and a senior Hamas official said.
A framework currently under negotiation by international mediators includes the initial swap of 40 living hostages, including female soldiers, invalids and older hostages, in exchange for hundreds of Palestinians detained in Israeli prisons.
There are about 100 living hostages remaining in Gaza, according to Israeli officials. It was not immediately clear if Israel would now demand that young men and soldiers be included among the first 40 released captives. Those hostages had been expected to have to wait for a later phase of the deal.
Amid the talks for a cease-fire to the conflict in Gaza, Iran and Israel have traded fresh threats in recent days, increasing fears of a wider regional war.
Iran has vowed to retaliate for Israel’s April 1 strike on an Iranian Embassy building in Damascus, Syria, that killed several senior Iranian military commanders.
The Israeli strike in Damascus was among the most significant attacks in a yearslong shadow war between Israel and Iran that has included the assassinations of Iranian military leaders and nuclear scientists. Israel blames Iran for supporting and arming proxy militias hostile to Israel across the region, such as Hamas in Gaza and Hezbollah in Lebanon.
Iran’s supreme leader, Ayatollah Ali Khamenei, reiterated threats of retribution against Israel in a speech he made on Wednesday for Eid al-Fitr. Attacking an embassy building, he said, “means that they have attacked our soil.”
“The evil regime made a mistake and it should be punished and will be punished,” he added, according to IRNA, the state news agency.
The response from Israel’s foreign minister, Israel Katz, was swift: “If Iran attacks from its territory, Israel will react and attack in Iran,” he wrote in Persian on X, tagging Mr. Khamenei in his post.
Israel has not publicly taken responsibility for the strike in Damascus, but several Israeli officials have confirmed the country’s involvement.
U.S. officials have said they were bracing for a possible Iranian response.
President Biden has been increasingly critical of Israel’s prime minister, Benjamin Netanyahu. On Wednesday he told reporters that he had been “blunt and straightforward” with Mr. Netanyahu when they spoke last week after the killing of seven aid workers by Israeli forces, making clear that Israel had to change its conduct of the six-month war or face consequences.
Mr. Biden on Wednesday reiterated his call on Israel to “do more” in facilitating humanitarian aid into Gaza. “We’ll see what he does in terms of meeting the commitments he made to me,” Mr. Biden said of Mr. Netanyahu.
Tensions between the Biden administration and Israel’s government have risen as the death toll in Gaza has climbed beyond 33,000. In an interview that aired Tuesday night, Mr. Biden called Mr. Netanyahu’s approach to the war a “mistake.”
In the interview, which was recorded last Wednesday and aired on Univision, Mr. Biden again referred to the strike on the aid workers as “outrageous,” and he said he did not approve of Mr. Netanyahu’s approach to the war.
“I think what he’s doing is a mistake. I don’t agree with his approach,” Mr. Biden said, echoing remarks he made last month. “What I’m calling for is for the Israelis to just call for a cease-fire.”
Israel has acknowledged that the killing of the seven aid workers from the World Central Kitchen was a result of a series of mistakes within the military. The Univision interview was recorded two days after that strike and the day before Mr. Biden and Mr. Netanyahu had a tense 30-minute phone call.
On that call, Mr. Biden threatened to condition future support for Israel on how it addressed his concerns about civilian casualties and the humanitarian crisis in Gaza. That prompted Israel to commit to allowing more food and other supplies into the besieged territory, including reopening the Erez crossing between Israel and northern Gaza for aid delivery.
The United Nations says that a human-made famine is looming in Gaza, and many experts say that conditions in northern Gaza, which has mostly been cut off from aid deliveries since early in the war, already meet the criteria for a famine. In that part of the territory, a few hundred thousand people are surviving on an average of 245 calories a day, according to Oxfam, an aid group.
The focus of the Israeli military appears to be in the south, where Israeli leaders say they are gearing up for an incursion into Rafah, which shares a border with Egypt and is swollen with more than a million displaced Palestinians. Rafah is also home to what the Israeli military says are Hamas battalions that it has vowed to destroy.
Adam Rasgon and Peter Baker contributed reporting.
