The Biden administration and other allies have been putting pressure on Israel to move away from the large-scale air and ground assaults that have led to large numbers of casualties in Gaza and brought about a scale of humanitarian suffering that international agencies and aid groups are running out of superlatives to describe.

The United Nations secretary general, António Guterres, said Monday that Israel’s campaign in Gaza had “unleashed wholesale destruction and levels of civilian killings at a rate that is unprecedented during my years as secretary general.”

“Nothing can justify the collective punishment of the Palestinian people,” Mr. Guterres said. He joined others in warning of the imminent risk of famine for the enclave’s 2.2 million civilians, saying: “The long shadow of starvation is stalking the people of Gaza.”

Mr. Gallant, a member of Prime Minister Benjamin Netanyahu’s war cabinet, is a moderate member of Mr. Netanyahu’s right-wing Likud party. Earlier this month, he floated a postwar plan for Gaza that appeared to diverge from the party’s far right, calling for a “multinational task force” to oversee the reconstruction and economic development of the territory while Israel maintains military control of its borders.

Biden administration officials have said repeatedly that the Palestinian Authority should have a role in postwar governance, a view that some Israeli leaders have rejected.

Mr. Gallant said on Monday that a “diplomatic path” needed to be in place for the end of the military campaign and called for compromises among Israel’s leadership, saying “indecisiveness” would hamper the country’s military gains.

Mr. Gallant reiterated that despite the change in pace, the fighting would go on as long as needed for Israel to achieve its war aims. Only continued military pressure would lead to the release of the hostages still being held in Gaza, he said.

Johnatan Reiss contributed reporting.

“If we are just focusing on the symptoms and not treating the real issue, it will be temporary,” he said, arguing that the U.S.-led campaign of strikes in Yemen last weekend will create “a high risk of further escalation.”

Qatar, a close U.S. ally, has played a key role in negotiations with Hamas, the Palestinian armed group that controls Gaza and launched the Oct. 7 attacks in Israel, killing around 1,200 people, according to Israeli officials. In response to the attacks, the Israeli military launched an aerial bombardment and ground invasion of Gaza that has killed more than 24,000 Palestinians, according to Gazan health authorities.

In the wake of that war, Yemen’s Houthi militia has propelled itself into an unlikely global spotlight by sowing chaos in the Red Sea, attacking commercial ships and hobbling global trade. The group — a once-scrappy tribal militia that is now the de facto government of northern Yemen — has portrayed its campaign of missile and drone attacks as a righteous battle to force Israel to end its siege of Gaza, although many of its targets have had no clear connection to Israel.

Dozens of U.S.-led strikes on Friday and Saturday hit Houthi installations in Yemen in an attempt to deter the group and curb its ability to launch attacks. But Yemeni experts and Arab officials have warned repeatedly that a military response would play into the Houthis’ agenda and fan the flames of regional conflict. After the strikes, the Houthis vowed to retaliate, and the group attacked a U.S.-owned commercial ship on Monday.

“We don’t care — make it a great world war,” Yemenis have chanted at Houthi rallies recently, reciting lines from a Houthi propaganda poem.

The Qatari prime minister’s remarks are the latest from a U.S. ally in the Middle East expressing deep concern about the implications of the U.S.-led strikes. On Friday, the foreign ministry of Oman publicly denounced the strikes.

In order to address the threat posed by the Houthis — whose attacks have stoked their domestic and regional popularity — the international community should focus on diplomacy and resolve “the main conflict in Gaza,” Sheikh Mohammed said.

“As soon as it’s defused, I believe everything else will be defused,” he said.

U.S. officials and those from allied Western governments have said the Houthis’ continuing attacks on ships left them with little choice but to respond.

Sheikh Mohammed also cautioned that Arab countries “normalizing” their relationships with Israel — a key goal of the Biden administration — would do little to tame conflict in the region unless a Palestinian state is created. The Israeli government remains publicly dismissive of that idea.

The international community’s response to the war in Gaza has been “very disappointing for the region and the people of the region,” he added.

“What kind of generation do we expect in our region — or even in Europe or elsewhere — watching all of these images and seeing the world just staying silent about it?” he said. “It will just create rage and anger.”

A separate ballistic missile attack hit targets in Syria connected to the Islamic State, the Guards said.

A statement by the elite Revolutionary Guard Corps said that the missile strike in Erbil had been aimed at “the destruction of espionage headquarters and places that anti-Iranian terrorist groups” used to plan a suicide bombing attack in Kerman, Iran, that killed 86 people this month at a memorial procession for Maj. Gen. Qassim Suleimani. The Guards also cited an assault in December on a police headquarters in Rask, Iran, that killed at least 11 officers.

Some Iranian leaders initially appeared to blame Israel for the attack at the Suleimani memorial, though the Islamic State claimed responsibility for it. In a statement later on Tuesday, the Revolutionary Guards appeared to return to the narrative that blamed Israel, saying the target in Erbil had been the local headquarters for Mossad, Israel’s spy agency. Israel did not immediately respond.

The attacks at the memorial and at the police station were seen as signs of Iran’s vulnerability to infiltration by extremist groups despite its formidable intelligence service and police capabilities.

Direct attacks by the Iranian Revolutionary Guard Corps, while not new, have been far less frequent than those conducted by Iran’s proxies. Those militant groups have launched at least 130 assaults on U.S. installations in Iraq and Syria since the war in the Gaza Strip began in October, after Hamas led an attack in southern Israel that, Israeli officials say, killed 1,200 people. Israel retaliated by bombarding the strip, killing more than 23,000 people and displacing millions, according to Gazan health officials.

Several of the explosions early Tuesday occurred near a new U.S. Consulate in Erbil under construction, and several other explosions happened near the Erbil airport. An American official said: “No U.S. facilities were impacted. We’re not tracking damage to infrastructure or injuries at this time.”

The U.S. State Department said: “The United States strongly condemns Iran’s attacks in Erbil today and offers condolences to the families of those who were killed. We oppose Iran’s reckless missile strikes, which undermine Iraq’s stability.

Erbil is the capital of the Kurdistan region of Iraq and is its most populous city. The Kurdish region’s security council called on the international community to condemn the Iranian attack, which it described as “a blatant violation of the sovereignty of the Kurdistan region and Iraq and the federal government.”

In a statement, the council said that “Erbil is a stable region and has never been a threat to any party,” adding: “The Revolutionary Guard said that the attack targeted several sites of Iranian opposition groups. Unfortunately, they always use baseless excuses to attack Erbil.”

Kifah Mahmood, a former media adviser to Massoud Barzani, the retired longtime leader of Kurdistan, said the Revolutionary Guards had been trying to “cover up their own security failure” in Kerman by staging a retaliatory attack. “But unfortunately,” he said, “the missiles landed on civilians and killed some, and injured others.”

The attacks occurred as Iranian-linked groups have been targeting U.S. bases and camps in Iraq and Syria, and Iranian proxy groups like the Houthi militants in Yemen have been attacking commercial shipping in the Red Sea amid Israel’s war against Hamas, the group that controls parts of the Gaza Strip. They are acting, the Houthis say, in solidarity with Palestinians in Gaza.

Those attacks have heightened tensions in the Middle East, and raised the risk that an already dangerous situation would flare into greater regional violence.

Falih Hassan contributed from Baghdad, and Eric Schmitt from Washington.

“We are investigating the event and its circumstances, examining the images distributed by Hamas, alongside additional information at our disposal,” he added.

The claim of the hostages’ deaths, in a video released by Hamas’s military wing, came after two taunting messages from the group promising news on Monday about the fate of three hostages — the two it later said were killed, and a third it said was injured.

A senior adviser to Prime Minister Benjamin Netanyahu of Israel declined to comment on the video, but the Israeli government has condemned such messages as psychological warfare.

The video included clips, apparently recorded earlier, of the two hostages who it claimed were killed, Yossi Sharabi, 53, and Itai Svirsky, 38, speaking while looking into a video camera, and then showed video apparently showing their bodies. It included narration by the hostage who reportedly survived, Noa Argamani, 26, who told of her companions’ deaths and described being wounded, herself.

It was not possible to determine when or where any scenes in the video were recorded.

Admiral Hagari, while not confirming the deaths, said that “in recent days,” the military had met with the men’s families “and expressed grave concern for their fate, due to information available to us.”

A previous video, released on Sunday, showed the three hostages identifying themselves by name and age, and ended with a caption that read: “Tomorrow we will inform you of their fate.”

Another video, released early Monday, featured headshots of the three hostages and said, “Tonight we will inform you of their fate.”

The videos appeared designed to taunt Israelis desperate for news of the hostages and to ratchet up pressure on the Israeli government to make concessions to secure their release. At the same time, the videos appeared to demonstrate the leverage which Hamas can exert on Israeli society through the hostages.

In a third video that announced the two deaths, Ms. Argamani addressed a camera while seated against a white background. It was not possible to determine whether she was speaking from a script that had been prepared for her; Mia Schem, a hostage released in late November, has said that Hamas dictated to her what to say for a video that was published in October.

Previous videos released by Hamas about the hostages have omitted or distorted crucial details.

Rights groups and international law experts say that any hostage video is, by definition, made under duress, and can constitute a war crime.

In the last of the three videos, Ms. Argamani said that she had been in a building with the two others when it was hit by three missiles fired by an Israeli warplane, with two exploding and burying them under rubble. She said that Hamas fighters dug her and Mr. Svirsky out but that Mr. Sharabi had been killed. She did not say when the attack happened.

She said that two nights later, she and Mr. Svirsky had been relocated to another location. En route, Mr. Svirsky was killed by an Israeli strike, she said, and she received shrapnel wounds to her head and body. The video ended with images of what appeared to be the two men’s dead bodies lying on white sheets.

Admiral Hagari later said that Mr. Svirsky had not been hit by Israeli forces.

“The building where they were being held was not a target, and it was not struck by our forces,” he said. “We did not know their real-time location; we do not strike in places where we know there may be hostages. In hindsight, we know we struck targets near to the location where they were being held.”

“I had it in my hand the entire time. I didn’t notice,” Hila said on Friday in an interview in New York, before she spoke at a rally in support of the remaining hostages. “When you’re afraid you don’t notice.”

Hila was one of more than 30 children kidnapped by Hamas on Oct. 7, and held until late November, when they, along with dozens of adults, were released during a brief truce. Hila, now 13, is the youngest of the returned hostages to speak out about the harsh conditions in which they were held, seeking to highlight the plight of more than 100 hostages who remain in Gaza.

The terrifying drive to Gaza, surrounded by Hamas terrorists, was the first time, Hila said, that she fully realized how “really close” the territory was to the community she had grown up in.

She said she, her mother and Emily were taken to a home in Gaza, where they were put in a dark room with a couple of other hostages. At first, an armed guard stayed in the room, but eventually moved to the living room.

“They understood we’re not going to run away,” Hila said. “Outside it’s dangerous too — why would we run?”

They were warned not to try to escape, Hila said, told that “if we go outside ‘the people out there don’t like you, so you’ll be killed anyway.’”

Their captors gave them little food — half a pita and a bit of halva on some days, canned beans on others — and very little water, often well water so distasteful, Hila said, that she had to force herself to drink.

At times, the captors ate while the captives did not, she said: “There were days when there just wasn’t food, and they would keep it for themselves.”

Occasionally, Hila said, they heard other children’s voices, and wondered if they were elsewhere in the home. They had to request permission to use the bathroom, and Hila learned the Arabic word for it, hammam.

Once, an explosion nearby caused the window of their room to break, Hila said, but they escaped injury.

A few times, she recounted, they were woken in the middle of the night and hastily moved in the darkness.

“They told us at first, ‘you’re moving to a safer place,’ ” Hila said. “But we didn’t know if we would be killed.”

The girls were told to keep quiet. Emily turned 9, and Hila’s own birthday was nearing. They tried to keep themselves occupied, with drawing or games.

“We played cards, but how much can you play cards, all day, every hour?” Hila said.

Freedom came suddenly, she said.

About a month and a half into their captivity, the captors suddenly separated the girls from Hila’s mother.

“Mom had started to be scared that something wasn’t OK, that they weren’t taking her,” Hila said, adding, “and then they just came and took us, and she stayed.”

The girls were then released and returned to Israel. The separation of mother and child violated the terms of the exchange deal, drawing outrage in Israel. Raaya was ultimately released several days later, just after Hila’s 13th birthday.