A senior official of the UN agency for children, who is visiting Japan, has described the Gaza conflict as "a war on children" and called for an immediate ceasefire to save them.

Adele Khodr, the UNICEF regional director of its office in the Middle East and North Africa, spoke to reporters in Tokyo on Monday.

She said about 37,000 children are suffering from serious malnutrition due to a food shortage, and some 17,000 are facing risks of exploitation and abuse after losing their parents or other guardians.

Khodr said the conflict is "a war on children," pointing out that wherever there is an attack, children are killed because Gaza has a very young population in a very small area.

She also called the enclave a graveyard for children, and said "the situation is really very bad."

She said if injured children had been sent to a hospital equipped with medical supplies and equipment, their lives could have been saved and many of them would not have lost their limbs.

Khodr stressed the need for a ceasefire. She said if the war continues, it's not possible to talk about the transportation of supplies or to plan anything.

Gaza authorities say that as of Friday more than 37,200 people have died in the conflict, and nearly 16,000, or more than 40 percent, of them were children. They also say about 34,000 children have been injured and about 1,500 have lost limbs or suffered other severe disabilities.