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 U.S. Embassy said it'll offer transportation for Americans looking to leaving Israel beginning on Friday.

"It will take some period of time to schedule everyone seeking to depart," the embassy said. "Transportation will be by air to Athens or Frankfurt, or sea from Haifa to Cyprus. You will not be able to choose your destination – we will assign you to the next available flight or ship."

"You should be prepared to depart within 8-12 hours of receiving notice of your booking. Each traveler may bring one small carry on item no more than 22 pounds (10 kg) and one suitcase no more than 35 pounds (16 kg)," the embassy said.

Delta Air Lines said it's partnering with the government to help set up flights through Athens.

United Airlines said it's adding extra flights with capped fares between Athens and Newark, New Jersey, and will use a larger plane for its Athens to Washington flight. "We’re in close touch with the U.S. State Department as it seeks to add additional options for Americans traveling from the region," United said.

American Airlines also said it is working "closely" with the State Department on its needs.

The U.S. expects "these initial travel options to facilitate the safe departure of thousands of U.S. citizens per week," State Department spokesperson Matthew Miller said in a statement.

A separate official said that the State Department remains in contact with "several thousand" American citizens in Israel, but it’s unclear how many will ultimately decide to leave. Some have already departed.

The State Department estimates that roughly 500,000 American citizens live in Israel.

-ABC News' Amanda Maile, Will Gretsky and Shannon Crawford