Neither the White House nor the State Department has directly addressed the report, which blamed Israeli restrictions on aid, among other factors, for the famine. Prime Minister Benjamin Netanyahu of Israel on Friday called the report “an outright lie,” saying that Israel had “gone to unprecedented lengths to enable aid to go into enemy territory.”

Mike Huckabee, the U.S. ambassador to Israel, echoed Mr. Netanyahu’s criticisms on social media. “Tons of food has gone into Gaza but Hamas savages stole it, ate lots of it to become corpulent,” he wrote on X.

The release of the report capped a week in which the Trump administration backed Mr. Netanyahu’s government on several issues, or mostly stayed silent, even as many of Israel’s allies condemned its actions in increasingly harsh terms.

American pressure is one of the few levers left that could persuade Mr. Netanyahu to change Israel’s conduct in the nearly two-year war against Hamas in Gaza, according to analysts.

Mr. Netanyahu is “clearly more comfortable with the fact that Donald Trump is not going to impose costs or consequences that would constitute real pressure,” said Aaron David Miller, a former U.S. diplomat who joined negotiations between Israelis and Palestinians during the 1990s.

At times, Mr. Trump has appeared willing to break with Mr. Netanyahu, cutting a deal with Iranian-backed Houthis to stop attacks on ships and negotiating directly with Hamas for the return of American hostages. In late July, he publicly said he believed that there was starvation in Gaza.

“This is not a crisis of a few isolated children; every child is at risk,” said Tess Ingram, a spokeswoman for UNICEF, the United Nation’s children’s organization.

After months of warnings, the Integrated Food Security Phase Classification, a panel of food security experts backed by the United Nations, said Friday that it had found that Gaza City and its surrounding areas were suffering from famine. The report warned that central and southern Gaza also could also face famine by September.

Israel said it was doing everything possible to deliver food to Gaza, noting that prices in local markets had dropped since Israel began funneling more aid into the enclave in late July. Israeli officials have said they let in enough food into Gaza, but argue that aid agencies are struggling to distribute it properly.

In a statement, Mr. Netanyahu acknowledged that there had been some “temporary shortages” but said they had been swiftly remedied.

Hani al-Dibs, a 44-year-old teacher in Gaza City, said the price of some goods like flour and canned vegetables had dropped over the past few weeks. But he said many items were still prohibitively expensive for people impoverished by nearly two years of war.

Mr. al-Dibs said he was feeding his children two small meals a day, often using canned beans and lentils. Despite the searing summer heat, trucks bearing potable water tended to arrive just twice a week, he added. “This is our life now, and we have to make do.”

Israel and the United States have also backed their own, much-criticized aid initiative in Gaza, in which American security contractors oversee the distribution of boxes of food at sites behind Israeli military lines. Hundreds of people have been killed near the sites, according to Gaza health officials.

Many of Israel’s other traditional allies, including Britain, were skeptical of Israel’s response to the report.

At the same time, Israel is preparing for a full-scale assault on Gaza City, where the committee said it had found evidence of famine. Aid agencies have warned that the attack could force hundreds of thousands of people to flee, precipitating an even deeper humanitarian crisis.

Mr. Netanyahu argues that the operation is necessary to rout Hamas, which has fought a guerrilla insurgency against Israeli forces. But the Israeli public is divided, with many calling for an immediate cease-fire with Hamas that would free the hostages still held in Gaza.

While U.S. negotiators seek to revive the moribund negotiations for a truce between the two sides, Mr. Trump appeared this week to back Israel’s planned assault in Gaza.

This week, Israeli authorities also approved the contentious E1 settlement project, which would involve the construction of about 3,400 new housing units in the central West Bank. Roughly 500,000 Israeli settlers live among three million Palestinians in the Israeli-occupied territory.

The E1 project had been delayed for about two decades under U.S. pressure. Critics say it would bisect the West Bank, posing a major challenge for the contiguity of any future Palestinian state.

France, Britain, Australia and more than a dozen other countries immediately denounced the plan as illegal and a violation of international law. The Trump administration, however, stayed largely silent. Mr. Huckabee told Israeli radio that the move was fundamentally Israel’s decision.