The health ministry in Hamas-run Gaza said on Friday that hospitals have only two days' fuel left before they must restrict services, after the United Nations warned aid delivery to the war-devastated territory is being crippled.

The warning came a day after the International Criminal Court issued arrest warrants for Israeli Prime Minister Benjamin Netanyahu and former defence minister Yoav Gallant more than a year into the Gaza war.

The UN and others have repeatedly decried humanitarian conditions, particularly in northern Gaza, where Israel said on Friday it had killed two commanders involved in Hamas's October 7, 2023 attack that triggered the war.

Gaza medics said an overnight Israeli raid on the cities of Beit Lahia and nearby Jabalia resulted in dozens killed or missing.

Marwan al-Hams, director of Gaza's field hospitals, told reporters all hospitals in the Palestinian territory "will stop working or reduce their services within 48 hours due to the occupation's (Israel's) obstruction of fuel entry".

World Health Organization chief Tedros Adhanom Ghebreyesus said he was "deeply concerned about the safety and well-being of 80 patients, including 8 in the intensive care unit" at Kamal Adwan hospital, one of just two partly operating in northern Gaza.

Late Thursday, the UN's humanitarian coordinator for the Palestinian territories, Muhannad Hadi, said, "The delivery of critical aid across Gaza, including food, water, fuel and medical supplies, is grinding to a halt."

He added that for more than six weeks, Israeli authorities "have been banning commercial imports" while "a surge in armed looting" has hit aid convoys. (AFP)