The U.S. claimed Saturday that Israel has in principle agreed on a cease-fire deal with Hamas while the first American airdrops of humanitarian aid reached besieged Gaza.

The framework agreement envisages a six-week cessation of hostilities, which could begin immediately if the Palestinian resistance group signs off on the release of the most vulnerable hostages it holds, a senior U.S. official told reporters on a call.

"The Israelis have more or less accepted it," the administration official said. "Right now, the ball is in the camp of Hamas."

The announcement came hours after U.S. military cargo planes began airdropping humanitarian aid into the besieged Gaza Strip.

The United Nations has warned of famine in Gaza and earlier this week Israeli forces shot and killed more than 100 people scrambling for food aid.

Saturday's drop, which included 38,000 meals, was conducted "to provide essential relief to civilians affected by the ongoing conflict," the U.S. Central Command (CENTCOM) said.

A CENTCOM official told AFP that the meals were made up of U.S. military rations that did not contain pork, the consumption of which is prohibited by Islam.

Working round the clock

Negotiators from regional powers have been working around the clock to secure a Gaza truce by the start of the Islamic holy month of Ramadan in about one week.

"It will be a six-week cease-fire in Gaza starting today if Hamas agrees to release the defined category of vulnerable hostages ... the sick, the wounded, elderly and women," the administration official said.

Hamas members took about 250 hostages during their unprecedented cross-border incursion on Israel on Oct. 7, 130 of whom remain in Gaza, including 31 whom Israel says are presumed dead. It was unclear how many of the remaining hostages are deemed vulnerable.

The United States hopes any truce would create space for a more enduring peace. A Hamas delegation was expected to fly to Cairo on Saturday for talks on a truce, a source close to the group told AFP.

The administration official said a cease-fire would also allow a "significant surge" in humanitarian aid to Gaza, with airdrops not seen as a replacement for full-scale relief convoys.

"None of these – maritime corridors, airdrops – are an alternative to the fundamental need to move assistance through as many land crossings as possible. That's the most efficient way to get aid in at scale," a second U.S. official told reporters.

The U.N. Security Council issued a statement Saturday voicing "grave concern" over the acute food insecurity in Gaza and urging the unfettered delivery of humanitarian aid "at scale."

Key ground route

Hundreds of protesters rallied in Washington on Saturday, shouting slogans like "Free free Palestine" outside the Israeli embassy before marching with a giant Palestinian flag to the Israeli ambassador's residence.

Some held signs paying tribute to the U.S. airman who died after self-immolating outside the Israeli embassy last weekend, shouting "Free Palestine" as he lit himself on fire, according to footage shared on social media.

The Oct. 7 Hamas incursion resulted in the deaths of around 1,160 people, according to official figures.

Israel responded with a brutal assault on Gaza that has killed more than 30,000 people, according to the territory's Health Ministry.

The amount of aid brought into Gaza by truck has plummeted during nearly five months of the conflict and Gazans are facing dire shortages of food, water and medicines.

Some foreign militaries have airdropped supplies to Gaza, sending long lines of aid pallets floating down into the war-torn territory on parachutes.

Jordan has been conducting many of the operations with the support of countries including Britain, France and the Netherlands, while Egypt sent several military planes on an airdrop Thursday together with the United Arab Emirates.

Biden has pushed Israel to reduce civilian casualties and allow aid in, while at the same time, he has maintained military assistance for the key U.S. ally.

National Security Council spokesperson John Kirby described the airdrops as a "tough military operation" that required careful planning by the Pentagon for the safety of both Gazan civilians and U.S. military personnel.