At least 27 Palestinians were killed near a Gaza food distribution hub operated by a controversial U.S.-backed group, the enclave's Hamas-run health ministry says.

Palestinians on their way to receive aid from a distribution site in southern Gaza have come under fire for a third consecutive day, with nearly 30 people killed and dozens wounded, according to the Palestinian Ministry of Health and Nasser hospital.

Officials said Hamas was seeking changes on guarantees for a permanent end to war. That has long been the core sticking point with Israel.

The latest friction in negotiations comes as the fighting nears 20 months of war, and as desperation grows among hungry Palestinians and relatives of hostages in Gaza.

The group said it sought a permanent ceasefire and a withdrawal of the Israeli military from Gaza, though additional details were not immediately available.