The Israel Defense Forces said its fighter jets have killed Iman Nofal, a senior Hamas member who was a former leader of Hamas' military intelligence.

Gaza hospitals are estimated to have less than 24 hours of fuel left, according to the United Nations Relief and Works Agency.

President Joe Biden departs for the Middle East on Tuesday for in-person meetings with Israeli and Arab leaders amid concerns of an expanded conflict in the Israel-Hamas war.

National Security Council spokesman John Kirby told "Good Morning America" that Biden's focus is on the hostage situation, to make sure humanitarian aid can flow to civilians in Gaza, and to get an update from Israeli counterparts on their plans and ground operations.

Asked about safety concerns, Kirby said "there’s always a concern" wherever the president goes, and those concerns would be "appropriately addressed through the necessary force protection and personnel protection measures. "

Asked if Biden's visit also includes urging Israel to avoid a full-scale ground invasion of Gaza, Kirby reiterated that the U.S. is not telling the Israeli military how to operate but that civilians should be protected.

Kirby added that it's "vital" that the administration gets supplemental funding from Congress for Israel and Ukraine.

-ABC News' Justin Gomez

The Egyptian Food Bank has nearly 3,000 tons of aid, including food, medicine and blankets, ready to cross into Gaza to help its trapped residents, its CEO said. But for now, the trucks are sitting still as the Gaza-Egypt border remains closed.

Mohsen Sarhan, the CEO of the Egyptian Food Bank, told ABC News he went to the border on Tuesday morning.

"You can see people dying, like, few miles away from you," he said. "Everyone in the world knows that these people have run out of water, and they have run out of medicine and have they have run out of food. And you have all that right in front of you. And you can't give it to the people. It's a human rights crisis. And it's very frustrating."

-ABC News' Matt Rivers

The World Health Organization is begging Israel to immediately reverse its evacuation order for the over 1 million living north of Wadi Gaza, saying "a mass evacuation would be disastrous for patients, health workers and other civilians left behind or caught in the mass movement."

"With ongoing airstrikes and closed borders, civilians have no safe place to go," the WHO said in a statement. "Almost half of the population of Gaza is under 18 years of age. With dwindling supplies of safe food, clean water, health services, and without adequate shelter, children and adults, including the elderly, will all be at heightened risk of disease."

"Of the thousands of patients with injuries and other conditions receiving care in hospitals, there are hundreds that are severely wounded and over 100 who require critical care," the WHO said. "Many thousands more, also with wounds or other health needs, cannot access any kind of care. The compressed timeframe, complex transport logistics, damaged roads, and, above all, lack of supportive care during transport all add to the difficulty of moving them."