While the International Court of Justice, or World Court, has no means to enforce its orders, the case was a stark sign of Israel's global isolation over its campaign in Gaza, particularly since it began its offensive against Rafah this month against the pleas of its closest ally the United States.
Reading out the ruling, World Court president Nawaf Salam said the situation in the Palestinian enclave had deteriorated since the court last ordered Israel to take steps to improve it, and conditions had been met for a new emergency order.
"The state of Israel shall (...) immediately halt its military offensive, and any other action in the Rafah governorate, which may inflict on the Palestinian group in Gaza conditions of life that could bring about its physical destruction in whole or in part," he said.
Israel had not explained how it would keep the population safe during an evacuation of Rafah, or provide food, water, sanitation and medicine for the 800,000 Palestinians that had already fled the Israeli advance, he said.
The ICJ ordered Israel to open the Rafah crossing between Egypt and Gaza to let in aid. Israel, it added, must provide access for investigators and report back on its progress within one month.
The order was adopted by the panel of 15 international judges in a 13-2 vote, opposed only by judges from Uganda and Israel itself.
The court said the situation in Gaza had deteriorated since it last ordered Israel to take steps. (AP PHOTO)
South Africa hailed the ruling as groundbreaking.
A White House spokesperson said: "We've been clear and consistent on our position on Rafah."
The internationally recognised Palestinian Authority said it represented a global consensus that the war must end, although presidential spokesman Nabil Abu Rudeineh said it did not go far enough because it did not halt fighting in other parts of Gaza.
Senior Hamas official Basem Naim told Reuters: "We call upon the U.N. Security Council to immediately implement this demand by the World Court into practical measures to compel the Zionist enemy to implement the decision."
Israelis responded with outrage. Far-right Finance Minister Bezalel Smotrich said that those demanding Israel stop the war were also demanding that it cease to exist, which Israel would not agree to.
Israeli opposition leader Yair Lapid called the order "a moral collapse and a moral disaster" for failing to link the demand to halt fighting to a demand that Hamas free hostages.
The order was handed down a week after it was requested by South Africa as part of its case accusing Israel of violating the Genocide Convention enacted in the wake of the Holocaust.
The ICJ, based in The Hague, is the highest UN body for hearing disputes between states. Its rulings are final and binding but have been ignored in the past, as the court has no enforcement powers.
Israel's assault on Rafah has forced hundreds of thousands of Palestinians to flee the city. (AP PHOTO)
Israel has repeatedly dismissed the case's accusations of genocide as baseless, arguing in court that its operations in Gaza are self-defence and targeted at Hamas militants who attacked Israel on October 7.
Israel started its armoured attack on Rafah earlier in May, forcing hundreds of thousands of Palestinians to flee a city that had become a refuge to around half of the population's 2.3 million people.
Rafah, on Gaza's southern edge, has also been the main route in for aid, and international organisations say the Israeli operation has cut off the enclave and raised the risk of famine.
Israel says Rafah has served as the last redoubt for thousands of Hamas fighters and their senior commanders, and it cannot achieve its war aim of wiping out the Islamist militant group and rescuing its hostages without storming the city.
So far, fighting has taken place on Rafah's southern edge and eastern districts, but Israel has yet to begin an assault on the city's main populated area. Its closest ally, the US, has repeatedly called on it not to do so, saying Israel has yet to show a credible plan for how this can be done without causing mass casualties among the displaced people sheltering there.
Israel launched its air and ground war on Gaza after Hamas-led militants stormed into southern Israeli communities, killing around 1200 people and seizing more than 250 hostages, according to Israeli tallies. More than 35,000 Palestinians have since been killed in the offensive, Gaza's health ministry says.
