The UN humanitarian office said Israeli authorities were blocking its efforts to help people who had stayed in the north, Reuters reports.

“We have systematic refusal from the Israeli side of our effort to get there,” said Andrea De Domenico, Head of Office for the United Nations Office for the Coordination of Humanitarian Affairs in the Occupied Palestinian Territories.

“In particular, they have been very systematic to not allowing us to support hospitals, which is something that is reaching a level of inhumanity that, for me, is beyond comprehension,” he said.

Israel says it does not block aid and blames holdups on what it says are poor logistics by the UN and other aid agencies. Aid officials say Gazans are on the verge of starvation and suffering from diseases brought on by a lack of fresh water and sanitation due to widespread bombing.