Here’s the latest on the war.

With the humanitarian situation growing more desperate in Gaza, the Rafah crossing between the blockaded territory and Egypt still hasn’t opened to aid, a day after a United Nations-led deal appeared to have had laid the groundwork to allow trucks carrying humanitarian supplies to enter.

Diplomats familiar with back-channel talks were pessimistic about it opening at all on Friday, amid ongoing disagreements between Egypt and Israel on issues including how to institute a regular schedule of aid convoys, whether to allow in fuel and how to screen the convoys for arms.

The U.N. secretary general, António Guterres, visited the Rafah crossing on Friday and said talks were underway “with all the parties” to clarify any conditions on the movement of aid.

Gaza had already been living under a 16-year blockade by Israel and Egypt when Israel responded to the Hamas attack that killed 1,400 people this month with airstrikes and a “complete siege” of the enclave. Now, nearly half of the more than two million people living in Gaza have been displaced, according to the United Nations, and essential supplies like food and fuel are running out ahead of a widely anticipated Israeli ground invasion.

Previous agreements to provide aid have fallen through, but President Biden has said that Israel and Egypt had agreed to let through trucks full of food, water and medicine that are waiting in Egypt.

Here are other developments:

• In an Oval Office address on Thursday night, Mr. Biden linked Israel and Ukraine as he made his case for providing aid to both countries, saying that they face threats of annihilation by tyrants and terrorists. Mr. Biden is expected to request $14 billion in military and security aid to Israel for its war against Hamas and $60 billion for Ukraine to fight Russia, according to people familiar with the administration’s plans.

• American intelligence agencies have assessed that an explosion at a Gaza hospital on Tuesday killed 100 to 300 people — a more conservative estimate than that given by the health ministry run by Hamas — and that the hospital was lightly damaged, according to an unclassified report drafted by U.S. intelligence agencies on Wednesday.

• Israel’s military said it had been in contact with the families of 203 people taken hostage, raising the number of people believed to be held in Gaza. A leader of Hamas says that not all of the Israeli hostages who were taken to Gaza are being held by the group, a claim that will most likely complicate negotiations for their release.

• The U.S. State Department issued a rare worldwide travel advisory on Thursday, urging Americans to “exercise increased caution” because of heightened global tensions and the potential for terrorist attacks, demonstrations and violence “against U.S. citizens and interests.”

• A U.S. Navy warship in the northern Red Sea on Thursday shot down three cruise missiles and several drones launched from Yemen that might have been headed toward Israel, the Pentagon said. The incidents underscored the risks that the conflict between Israel and Hamas could spiral into a wider war.