An Israeli military incursion into Gaza's southern city of Rafah could lead to a "bloodbath", the World Health Organization warned Friday, announcing contingency plans.
Israeli Prime Minister Benjamin Netanyahu has vowed to crush Hamas's remaining fighters in Rafah, where much of Gaza's population has sought refuge from nearly seven months of war.
WHO director-general Tedros Adhanom Ghebreyesus warned of possible dire implications for the 1.2 million people sheltering in Rafah.
"WHO is deeply concerned that a full-scale military operation in Rafah, Gaza, could lead to a bloodbath, and further weaken an already broken health system," Tedros said on X, formerly Twitter.
In a statement, the WHO announced contingency efforts, but warned "the broken health system would not be able to cope with a surge in casualties and deaths that a Rafah incursion would cause".
"This contingency plan is Band-Aids," Rik Peeperkorn, the WHO representative in the Palestinian territories, told reporters in Geneva. "It will absolutely not prevent the expected substantial additional mortality and morbidity caused by a military operation."
According to the WHO, most of the besieged territory's health facilities have been damaged or destroyed amid heavy Israeli bombardment.
Only 12 of Gaza's 36 hospitals and 22 of its 88 primary health facilities are "partially functional", the UN health agency said.
"As part of contingency efforts, WHO and partners are urgently working to restore and resuscitate health services," the statement said.
It added that Rafah's three currently operational hospitals would become unreachable "when hostilities intensify in their vicinity".
Instead, the WHO is working to restore south Gaza's largest hospital, the Nasser Medical Complex in nearby Khan Yunis, and establish additional medical sites.
"The ailing health system will not be able to withstand the potential scale of devastation that the incursion will cause," Peeperkorn said.
A military operation in Rafah could spark a new wave of displacement, leading to more overcrowding, limited access to food, water and sanitation and more outbreaks of disease, he added.
In its statement, the WHO called "for an immediate and lasting ceasefire and the removal of the obstacles to the delivery of urgent humanitarian assistance into and across Gaza, at the scale that is required."
Jens Laerke, spokesman for the UN humanitarian agency OCHA, said that a military operation in Rafah "could lead to a slaughter".
"For agencies already struggling to provide humanitarian aid in Gaza, a ground invasion would strike a disastrous blow," he told reporters.
"Any ground operation would mean more suffering and death."
The bloodiest-ever Gaza war started after an unprecedented attack on southern Israel by Palestinian militant group Hamas on October 7, 2023.
The attack resulted in the deaths of 1,170 people, mostly civilians, according to an AFP tally of Israeli official figures.
Militants also took about 250 hostages, of whom Israel estimates 128 remain in Gaza. The army says 35 of them are dead.
Israel's relentless retaliatory military offensive has killed more than 34,000 people in Gaza -- most of them women and children -- according to the health ministry in the Hamas-run territory.