"We're going to make sure you have what you need to protect your people, to defend your nation," Biden said.
He also said that Israel had agreed to allow humanitarian assistance to begin flowing into Gaza from Egypt.
Israel had cut off the flow of food, fuel, and water to the Gaza Strip. Mediators have been struggling to break a deadlock over providing supplies to desperate civilians, aid groups, and hospitals. An explosion at a Gaza Strip hospital compounded the suffering.
Shortly after Biden's remarks, Israel confirmed food, water, and medicine would begin to flow, though the timing wasn't immediately clear.
Biden said he had spoken with the Israeli cabinet “to agree to the delivery of life-saving humanitarian assistance of civilians in Gaza.”
“Let me be clear,” Biden said. If Hamas diverts or steals the assistance, they will have demonstrated once again that they have no concern for the welfare of the Palestinian people.”
Biden also said an additional $100 million in humanitarian assistance for Gaza and the West Bank.
There were conflicting claims about who was responsible for the hospital blast. Officials in Gaza blamed an Israeli airstrike. Israel denied it was involved and released a flurry of video and other unconfirmed information that it said showed the blast was instead due to a missile misfire by Islamic Jihad, another militant group operating in Gaza. The Islamic Jihad dismissed that claim.
The Associated Press has not independently verified any of the claims or evidence released by the parties.
Biden on Wednesday said data from his Defense Department showed it was 'not likely' a strike by the Israeli military.
“It appears as though it was done by the other team, not you,” Biden told Israeli Prime Minister Benjamin Netanyahu during a meeting. But he said there were “a lot of people out there” who weren’t sure what caused the blast, which sparked protests throughout the Middle East.
Biden had also scheduled to visit Jordan to meet with Arab leaders on Wednesday, but the summit was called off after the hospital explosion.
He told Netanyahu he was “deeply saddened and outraged” by the hospital explosion. But he also stressed that “Hamas does not represent all the Palestinian people, and it has brought them only suffering.” And he spoke of the need to find ways of “encouraging life-saving capacity to help the Palestinians who are innocent, caught in the middle of this.”
Biden reiterated the U.S. was firmly behind Israel.
“I want you to know you're not alone. We will continue to have Israel's back as you work to defend your people," Biden said. "We'll continue to work with you and partners across the region to prevent more tragedy to innocent civilians."
Netanyahu called the president's visit “deeply, deeply moving," adding, "I know I speak for all the people of Israel when I say thank you Mr. President, thank you for standing with Israel today, tomorrow, and always.”
Netanyahu said Biden had rightly drawn a clear line between the “forces of civilization and the forces of barbarism,” saying Israel was united in its resolve to defeat Hamas.
“The civilized world must unite to defeat Hamas," he said. U.S. officials on Wednesday also announced sanctions against a group of 10 Hamas members and the Palestinian militant organization’s financial network across Gaza, Sudan, Turkey, Algeria and Qatar.
Biden also met with Israeli President Isaac Herzog as well as with Israeli first responders and the families of victims and those being held captives by Hamas.
The possibility of improved relations between Israel and its Arab neighbors has dimmed considerably with the outbreak of the Israeli war on Gaza. Israel has been preparing for a potential ground invasion of Gaza.
At least 4,000 Palestinians have been killed by Israeli strikes in Gaza. Another 1,200 people are believed to be buried under the rubble, alive or dead, health authorities said.
Protests swept through the region after the blast at the hospital, which had been treating wounded Palestinians and sheltering many more who were seeking a refuge from the fighting.
Hundreds of Palestinians flooded the streets of major West Bank cities including Ramallah. More people joined protests that erupted in Beirut, Lebanon and Amman, Jordan, where an angry crowd gathered outside the Israeli Embassy.
Outrage scuttled Biden's plans to visit Jordan, where King Abdullah II was to host meetings with Palestinian President Mahmoud Abbas and Egyptian President Abdel Fattah el-Sissi. But Abbas withdrew in protest, and the summit was subsequently canceled outright.
Ayman Safadi, Jordan’s foreign minister, told a state-run television network that the war is “pushing the region to the brink.”
Jordan declared three days of mourning after the hospital explosion and Safadi said the summit was canceled after speaking with all leaders. He said they had wanted the meeting to produce an end to the war, which seems unlikely now, and to give Palestinians the respect they deserve.
Kirby said Biden understood the move was part of a “mutual” decision to call off the Jordan portion of his trip. He said Biden would speak to Abbas and el-Sissi by phone Wednesday as he returned to Washington.
There are also fears that a new front could erupt along Israel’s northern border with Lebanon, where Hezbollah operates. The Iran-backed organization has been skirmishing with Israeli forces.
Always a believer in the power of personal diplomacy, Biden's trip is testing the limits of U.S. influence in the Middle East at a volatile time. It's his second trip to a conflict zone this year, after visiting Ukraine in February.
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