An aid ship loaded with some 200 tonnes of food has set sail from Cyprus to Gaza, the international charity behind the effort said.
The shipment is a test for the opening of a sea corridor to supply aid to the territory, where starvation is spreading five months into the Israel-Hamas war.
World Food Kitchen, the charity founded by celebrity chef Jose Andres, posted on the X social media platform that a ship set sail on Tuesday.
Live footage from the Associated Press showed the ship being towed out of a harbour in the port city of Larnaca.
The US has separately announced plans to construct a sea bridge near Gaza in order to deliver aid, but it will likely be several weeks before it is operational.
The five-month-old war that was triggered by Hamas’ October 7 attack in southern Israel has killed over 30,000 Palestinians and driven some 80% of Gaza’s 2.3 million people from their homes.
The UN says a quarter of the population is starving.
The attack that sparked the war killed around 1,200 people, and militants took around 250 hostage.
Aid groups say it is nearly impossible to deliver aid in much of the territory because of Israeli restrictions, ongoing hostilities and the breakdown of law and order after the Hamas-run police force largely vanished from the streets.
Conditions are especially dire in northern Gaza, which has suffered widespread devastation and been largely cut off by Israeli forces since October.
Up to 300,000 Palestinians are believed to have remained there despite Israeli evacuation orders, with many reduced to eating animal feed in recent weeks.
On Monday, the first day of the normally festive month of Ramadan, children with pots lined up at a charity kitchen in the urban Jabaliya refugee camp.
Each was given a small portion of cooked carrots and sweet potatoes to break the dawn-to-dusk fast.
“Our children can’t find anything to eat,” said Bassam al-Haw, a volunteer. “No food, no water, no flour.”
The planned sea route has the support of the EU, the US, the UAE and other countries.
The US and other countries have also launched airdrops of aid in recent days, but such efforts are costly and unlikely to meet mounting needs.
Once the Open Arms ship nears Gaza, two smaller vessels will tow the barge to a jetty that World Central Kitchen is building.
World Central Kitchen then plans to distribute the food in northern Gaza.
Organisers said the jetty will be outside of northern Gaza but declined to provide further details.
Mr Andres told The Associated Press in a brief interview on Saturday evening that they want to keep the location secret to prevent large crowds from disrupting the delivery.
Scores of Palestinians were killed last month during a chaotic aid delivery in the north organized by Israeli troops, who fired on the crowd.
Israel said most of those killed were trampled to death, while Palestinian officials said most had been shot.
Israel, which controls Gaza’s coastline and all but one of its land crossings, says it supports efforts to deliver aid by sea and will inspect all cargo before it sets sail for Gaza.
European Commission President Ursula von der Leyen said it was the first time a ship had been authorised to deliver aid directly to Gaza since 2005 and that the EU would work with “smaller ships” until the US completes work on its floating port.
Cypriot foreign minister Constantinos Kombos said during a visit to Beirut that there is a “mechanism” in place for larger shipments, with the goal of “a more systematic exercise with increased volumes”.