A UN committee has accused Israel of "severe" breaches of a global treaty protecting children's rights, saying its military actions in Gaza had a "catastrophic" impact on them and are among the worst violations in recent history.

"The outrageous death of children is almost historically unique. This is an extremely dark place in history," Bragi Gudbrandsson, Vice Chair of the Committee, told reporters on Thursday.

"I don't think we have seen before, a violation that is so massive, as we’ve seen in Gaza. These are extremely grave violations that we do not often see," he said.

Over 41,000 people have been killed in Gaza since Israel launched its military campaign on Oct. 7. Palestinian health authorities said earlier this week that 11,355 of those killed in Gaza are children, based only on fully documented deaths.

Israel's delegation argued in a series of UN hearings earlier this month that the treaty did not apply in Gaza or the occupied West Bank and claimed that it was committed to respecting international humanitarian law.

The four-member UN Committee monitors countries' compliance with the 1989 Convention on the Rights of the Child - a widely adopted treaty that protects under 18s from violence and other abuses.