The WHO stressed that the forced evacuation of patients and medical staff will only worsen the situation and contribute to a humanitarian and public health disaster.
It also urged Israel to "immediately reverse evacuation orders to hospitals in northern Gaza," calling for "protection of health facilities, health workers, patients, and civilians."
The WHO reiterated its calls for "immediate and safe delivery of medical supplies, fuel, clean water, food, and other humanitarian aid into Gaza through the Rafah crossing," where life-saving assistance, including WHO's medical supplies, arrived earlier on Saturday and awaits entry.
Since 7 October, Israel has specifically targeted Palestinian emergency responders and medical facilities in the Gaza Strip on multiple occasions, damaging 15 medical centres, rendering two hospitals out of service, and killing at least 28 responders.
"We are in a critical situation," said Ashraf Al-Qidra, the spokesman for the Gaza health ministry. "Ambulances can't get to the wounded, the wounded can't get to intensive care, and the dead can't get to the morgue," he added.