GENEVA - The World Health Organization said on Tuesday three hospitals in Israeli-besieged northern Gaza had requested help with evacuating patients and that planning for that was under way, expressing regret that doing so would rob people of a lifeline.

Hospitals have come under bombardment in the Israel-Hamas conflict and all hospitals in the northern part of the enclave have effectively ceased functioning normally, although they continue to house some patients that could not flee and displaced Gazans.

"We’re looking at three hospitals right now in the north that asked to be evacuated but the important point is where to? There is no safe space," WHO spokesperson Christian Lindmeier told a Geneva press briefing, saying that southern hospitals were already full and suffering shortages.

He said the requests came from hospital staff who feared for their lives.

"That means the situation on the ground has grown so dire that the only other alternative is facing what they think is certain death as the hospitals are under attack...," he said.

"Taking away health care from people, is taking away the last resort, it's taking away the last piece of humanity. And that's what is happening right now."

The three hospitals were Al Shifa, from which a group of babies has already been rescued, Indonesian Hospital and Al Ahli Hospital, he said. "So far it's only in planning stages with no further details," he added, saying it required close coordination with parties to the conflict to ensure the convoy does not come under fire as happened to the International Red Cross and French medical charity Medecins Sans Frontieres.

At the same briefing, the U.N. children's agency (UNICEF) warned of the risk of "mass disease outbreak" that could cause child death rates to mount in the densely populated enclave where thousands of people are crammed into overcrowded shelters.

"If children's access to water and sanitation in Gaza continue to be restricted and insufficient, we will see a tragic – yet entirely avoidable – surge in the number of children dying," said UNICEF spokesperson James Elder.

Already, cases of diarrhoea in children under five years old have surged to 10 times the pre-conflict monthly average, he said.

The World Food Programme's Arif Husain said that people in Gaza were receiving just 1-3 liters of water a day, far below international standards for emergencies. No bottled water has arrived for displaced people in northern Gaza for over a week, he said, raising serious concerns about dehydration.

(Reporting by Emma Farge; Editing by Miranda Murray, Alex Richardson, William Maclean)