In a press conference on Friday, Guterres said: "the Israeli army acknowledged mistakes and announced some disciplinary measures against soldiers following this week's appalling killing of seven humanitarian workers from World Central Kitchen".

"But the essential problem is not who made the mistakes, it is the military strategy and procedures in place that allow for those mistakes to multiply time and time again," he said.

"Fixing those failures requires independent investigations and meaningful and measurable change on the ground," Guterres added.

Guterres said some 196 humanitarian aid workers – including more than 175 United Nations staff –- have been killed in six months of war in Gaza, "and we want to know why each one of them was killed".

The UN secretary general said an independent investigation can only work with cooperation from the Israeli authorities.

Guterres stated Israel has informed the UN it intends to allow a substantial increase of aid to be distributed in Gaza.

"I sincerely hope that these intentions are effectively and quickly materialized because the situation in Gaza is absolutely desperate,” he said. “Six months on, we are at the brink: of mass starvation, of regional conflagration, of a total loss of faith in global standards and norms," he added.

"It’s time to step back from that brink,” the U.N. chief said, reiterating his urgent appeals for an immediate humanitarian cease-fire and release of all remaining Israeli hostages taken captive on Oct. 7," Guterres said.