They said the entire Middle East region was now on a precipice and called for an immediate cessation of hostilities.

Israel launched an air and ground war in northern Gaza last month, in what has been described by health workers as a "genocide within a genocide."

"The situation unfolding in North Gaza is apocalyptic," said the joint statement from heads of organisations that form the UN Inter-Agency Standing Committee.

"The area has been under siege for almost a month, denied basic aid and life-saving supplies while bombardment and other attacks continue. Just in the past few days, hundreds of Palestinians have been killed, most of them women and children, and thousands have once again been forcibly displaced."

"The entire Palestinian population in North Gaza is at imminent risk of dying from disease, famine and violence."

They urged all parties fighting in the besieged Palestinian territory to protect civilians, and called on Israel "to cease its assault on Gaza and on the humanitarians trying to help".

"Humanitarian aid cannot keep up with the scale of the needs due to the access constraints. Basic, life-saving goods are not available. Humanitarians are not safe to do their work and are blocked by Israeli forces and by insecurity from reaching people in need," they said.

"Humanitarian relief must be facilitated, and we urge all parties to provide unimpeded access to affected people," while hospitals "should not turn into battlegrounds".

The statement was signed by the heads of the UN humanitarian, health, food, rights, migration, refugee, development, children and women's agencies, among others.

"The entire region is on the edge of a precipice. An immediate cessation of hostilities and a sustained, unconditional ceasefire are long overdue," they said.

Israel's relentless bombardment and ground invasion have killed 43,259 people in Gaza, mostly women and children, according to the territory's health ministry. The UN says the figures are reliable and confirms that most of the dead are women and children.

*This story was edited by Ahram Online.