GENEVA (AP) — International aid groups say they are ready to deliver thousands of truckloads of food, water and other supplies to besieged Gaza if a temporary cease-fire in the Israel-Hamas war takes hold.

Some hailed an important first step, but many said Wednesday that a four-day truce isn’t enough to meet overwhelming needs after seven weeks of fighting have displaced hundreds of thousands of Palestinians now living in miserable conditions.

Key details of the accord announced Wednesday remain unclear, including the mechanics of getting more aid to desperate civilians and escorting the first group of Israeli hostages out of Gaza where they have been held since Hamas’ October 7 rampage in Israel.

The cease-fire efforts hit a hurdle Wednesday when Israel’s national security adviser Tzachi Hanegbi said in a late-night announcement that the deal would not take effect before Friday, a day later than originally expected.

Aid groups say a key ambition is to get help to northern Gaza, which has been largely inaccessible and where nearly all hospitals stopped working during a blistering air and ground offensive by Israeli forces.

“The entire humanitarian sector is ready to scale up once everything is set,” said Tommaso Della Longa, a spokesman for the International Federation of Red Cross and Red Crescent Societies, an umbrella organization that amounts to the world’s largest humanitarian aid group.

The international community and aid groups have been trying to find ways to get aid into Gaza since Israel retaliated for Hamas’ slaying of some 1,200 people in Israel on October 7. The onslaught has killed at least 11,000 people in Gaza, health officials in the Hamas-controlled enclave say.

Della Longa lamented bottlenecks he said have confounded the delivery of already insuffient aid into Gaza. He said his umbrella group hoped a truce deal would include a faster track of aid shipments.

The only route for international humanitarian aid into Gaza since the start of the war has been through the Rafah crossing between Egypt and Gaza. Planeloads of supplies have been flown into the nearby Egyptian city of El-Arish, and trucks have queued up near Gaza.

Intense Israeli inspections of Gaza-bound trucks and cargo have slowed their entry.

Joel Weiler, executive director of Doctors of the World, a Paris-based relief organisation, said a four-day window was far too short.

“Even if the aid enters, it will take three four days to deliver to doctors to get it, and then the fighting starts again,” he said. “It’s a joke. It’s white-washing.”

Many humanitarians say shipments through Rafah amount to only a trickle compared to the total needs of Gaza’s 2.3 million people, and want the restoration of access through the Kerem Shalom crossing — the main entry point for commercial goods into Gaza from Israel. It has been shuttered since the conflict began.

“If Kerem Shalom doesn’t open, the logistical nightmare will continue forever,” said Jan Egeland, head of the Norwegian Refugee Council, an aid group with 53 workers in Gaza.

Spokesperson Shani Sasson of COGAT, the Israeli military body responsible for Palestinian affairs, said she was “not aware of any changes” at Israel’s Nitzana crossing with Egypt to accommodate greater aid deliveries during a truce. Nitzana is where Israeli authorities check aid trucks before they enter Gaza at Rafah.

Della Longa, of the Red Cross and Red Crescent, said freedom of movement for humanitarians is another concern.

“It’s not enough to open up a gate. After opening a gate, you need to create a safe humanitarian space where we can work,” he said.