United Nations and other aid officials warned on Saturday that a new U.N. Security Council resolution calling for stepped-up aid delivery to the increasingly hungry and sick civilians of the Gaza Strip would fail to stop the spiraling humanitarian crisis because it did not demand a full halt to the fighting.

The resolution approved on Friday directs the secretary general of the United Nations to appoint a special coordinator for aid to Gaza and establish a mechanism to speed up delivery of desperately needed food, water, fuel and medicine, but it does not mandate a truce.

Even if enough aid were to cross the border, aid officials said, without a cease-fire, they would be unable to distribute it amid Israel’s frequent airstrikes and a ground invasion that has turned much of the territory into an active combat zone.

“Right now, we cannot deploy humanitarian aid. It’s impossible,” said Guillemette Thomas, the medical coordinator for Doctors Without Borders in Jerusalem. “People need to be able to get food and water without the fear of being bombed or killed or shot at any moment,” she added. “We need to be able to move within the strip to access people.”

It was not clear on Saturday how soon the special coordinator for aid to Gaza would be appointed or what the first steps would be.

After 11 weeks of war, international alarm has risen over the plight of the territory’s more than two million people, increasingly cut off from the outside world, most of them displaced from their homes and packed into overcrowded, unsanitary conditions in apartments, shelters, hospitals, schools and makeshift camps. More than 20,000 Palestinians have been killed, according to the Gazan Health Ministry, about 70 percent of them women and children, mostly in the fierce Israeli aerial bombardment, according to the health authorities in Gaza.

Gaza’s entire population is in crisis or worse, the Integrated Food Security Phase Classification, an international partnership of aid organizations, said this past week, with the “highest share of people facing high levels of acute food insecurity” that it “has ever classified for any given area or country.” Human Rights Watch this week accused the Israeli government of “using starvation of civilians as a method of warfare,” which it called “a war crime.”

Israeli ground forces, which invaded northern Gaza two months ago, continue to fight deadly battles with Hamas fighters there, while pushing gradually deeper into central and southern Gaza, as well. The military has ordered a series of civilian evacuations from the areas of the most intense fighting, forcing people into a shrinking, densely packed fraction of Gaza.

The Israeli military says it does what it can to minimize civilian casualties while targeting Hamas, but it has repeatedly struck even those areas where it has told displaced people to flee for their safety.

The grueling pace of the war, the fact that Hamas still has tens of thousands of fighters, and the discovery that the group’s tunnel network is vaster than Israelis realized are stirring debate within Israel about whether the government’s stated goal of eradicating Hamas is even possible. The Israeli military says it is steadily grinding down the group, which planned and led the Oct. 7 assault on Israel that killed more than 1,200 people, while at the same time increasingly emphasizing that the war is nowhere near an end.

“It can take time to work in a secure manner, to protect the security of our forces — to expose, investigate, extract terrorists from underground, kill them inside the shafts, map the shafts, insert explosives,” Rear Adm. Daniel Hagari, the Israeli military spokesman, said in a televised briefing on Friday.

The U.N. Security Council resolution was meticulously negotiated to avoid objections from the United States, which had vetoed earlier resolutions calling for a cease-fire. The Biden administration has backed Israel’s position that stopping the offensive would allow Hamas to rearm and continue to threaten Israel, while also urging Israel to do more to protect civilians.

The new resolution, which passed after repeated delays with a vote of 13-0, with the United States and Russia abstaining, focused on aid delivery, not stopping the fighting. It called on the warring parties to “allow, facilitate and enable the immediate, safe and unhindered delivery of humanitarian assistance” to civilians in Gaza and to “create the conditions for a sustainable cessation of hostilities.”

“It is welcome, but only time will tell what real difference this resolution is going to make, and it needs to increase the humanitarian assistance that has been going into Gaza,” said Juliette Touma, a spokeswoman for U.N.R.W.A., the United Nations relief agency for Palestinians.

Before the war, about 500 trucks a day carried aid to Gaza, which has been under a partial blockade by Israel and Egypt since Hamas took control there in 2007, and U.N.R.W.A. has said that a minimum of 200 a day are needed to sustain the population. Israel cut off all deliveries for the first two weeks after the Oct. 7 attacks. They then resumed on a very limited basis, often no more than a few dozen truckloads per day, through the Rafah border crossing with Egypt.

Last week, after significant international pressure, Israel opened its only cargo crossing to aid trucks. In the past week, an average of about 135 trucks per day entered Gaza, according to the United Nations — more than earlier in the war, but still far short of the need. And the increased shipments have done nothing to overcome the challenge of distributing aid beyond the border.

“You can’t deliver humanitarian assistance under a sky full of airstrikes, and there is very little assistance coming in,” Ms. Touma said.

Another issue in delivering aid has been the inspection of trucks, and the Security Council resolution did not address that.

Israel has insisted on having its people thoroughly inspect each shipment to prevent the entry of any goods that could benefit Hamas. Aid groups say that process has slowed things down, which Israel denies. Previously proposed Security Council resolutions would have had the United Nations take over inspection.

“The resolution maintains Israel’s security authority to monitor and inspect aid entering Gaza,” Israel’s ambassador to the United Nations, Gilad Erdan, said after the vote.

The small amounts of aid entering Gaza and the complete collapse of the territory’s commercial sector mean that many families have exhausted their resources and are increasingly going hungry, according to aid groups and Gaza residents.

Fuel shortages have shut down most of the territory’s electric power, most of its hospitals, water desalination and pumping plants, and sewage treatment stations. Humanitarian groups report sharp increases in infectious disease.

The Israeli military said in a statement on Saturday that troops had lured dozens of Palestinian fighters into an ambush in the Issa neighborhood of Gaza City before killing them in a targeted airstrike. It also said that over 200 members of Hamas and Islamic Jihad were arrested by Israeli troops in Gaza over the past week. The claims could not immediately be verified.

The military has issued additional evacuation orders affecting more than 150,000 people in central Gaza, U.N.R.W.A. said on Saturday.

Gazans “are not pieces on a checkerboard — many have already been displaced several times,” wrote Thomas White, who runs the agency’s Gaza division, on the X platform. “The Israeli Army just orders people to move into areas where there are ongoing airstrikes. No place is safe, nowhere to go.”

Emphasizing the danger to aid workers in Gaza, Achim Steiner, the administrator of the United Nations Development Program, said in a statement that a 30-year veteran of the organization, Issam al-Mughrabi, had been killed in an airstrike on Friday near Gaza City, along with his wife and five children, aged 13 to 32. On Saturday, the U.N. said members of his extended family may have been killed also, but that could not be immediately confirmed.

Criticism of the war within Israel has been muted since the Oct. 7 assault shocked the country. But even some former senior Israeli security officials have begun to question publicly whether the stated goal — toppling Hamas’s rule in Gaza — is ultimately feasible.

“The war goals should be redefined given the achievements we’ve had so far and with a strategic outlook on what’s happening in the region and around the world,” said a retired Israeli general, Avi Mizrahi, in a radio interview on Friday, adding that he did not think the Israeli military “would reach every last Hamas member.”

Aaron Boxerman and Isabel Kershner contributed reporting.