South Africa accused Israel on Thursday of subjecting Palestinians to genocidal acts at the opening of hearings at the top United Nations court on a case brought against the devastating Israeli military campaign in Gaza.

In hearings at the International Court of Justice (ICJ), also known as the World Court, South Africa demanded an emergency suspension of Israel's aerial and ground offensive in the Palestinian enclave, which it said was aimed at bringing about "the destruction of the population" of Gaza.

"Israel has a genocidal intent against the Palestinians in Gaza," Tembeka Ngcukaitobi, advocate of the High Court of South Africa, told the court.

"That is evident from the way in which this military attack is being conducted," he said, adding: "The intent to destroy Gaza has been nurtured at the highest level of state."

Israel has rejected the accusations of genocide as baseless and accused Pretoria of playing "advocate of the devil" for Hamas, the Palestinian Islamist militant group Israel is waging war against in Gaza.

The 1948 Genocide Convention defines genocide as "acts committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group".

South Africa points to Israel's sustained bombing campaign that has killed over 23 000 people in the small, densely populated Gaza Strip, according to health authorities in the Hamas-rum territory.

"Every day, there is mounting, irreparable loss of life, property, dignity, and humanity for the Palestinian people," said Adila Hassim, advocate of South Africa's high court.

"Nothing will stop the suffering, except an order from this court." South Africa has demanded that the ICJ order Israel to suspend its military campaign.

Israel launched all-out war after a cross-border rampage on October 7 by Hamas militants in which Israeli officials said 1 200 people were killed and 240 taken hostage back to Gaza.

Justice Minister Ronald Lamola said South Africa condemned Hamas' October 7 assault, but added that any attack, even one involving atrocious crimes, was not a justification for violations of the Genocide Convention.

Post-apartheid South Africa has long defended the Palestinian cause, a relationship forged when the African National Congress' struggle against white-minority rule was cheered on by Yasser Arafat's Palestine Liberation Organisation.

EMERGENCY RULING

The ICJ is hearing South Africa's arguments on Thursday and Israel's response to the allegations on Friday.

It is expected to rule on possible emergency measures later this month. The court will not rule at that time on the genocide allegations - those proceedings could take years.

The ICJ's decisions are final and without appeal - but the court has no way to enforce them.

With the politically charged case attracting global attention, supporters of both sides of the case planned marches and rallies in The Hague.

Thousands of pro-Israel protesters marched in freezing temperatures in the city centre early on Thursday, carrying Israeli and Dutch flags and posters with images of people taken hostage by Hamas.

Heavy police presence made sure the pro-Israel march and a pro-Palestinian march, with red-and-green coloured smoke symbolising the Palestinian flag, were kept separate.

Gabi Patlis, a native of Tel Aviv who now lives in the Netherlands, said it was painful to hear Israel accused of genocide. "Especially after 7 October - we were the ones that were attacked," he told Reuters at the rally.

ISRAEL SAYS ALLEGATIONS BASELESS

Israeli forces launched their offensive after Hamas fighters carried out a lightning attack across the border in what became the deadliest day in Israel's 75-year history.

Since then, the offensive has laid much of the heavily built-up territory, and nearly all its 2.3-million people have been driven from their homes at least once, causing a humanitarian catastrophe.

Israeli Prime Minister Benjamin Netanyahu said on social media platform X: "I want to make a few points absolutely clear: Israel has no intention of permanently occupying Gaza or displacing its civilian population."

Israel has said it is waging war against Palestinian militants, not the Palestinian people.

In its court filings, South Africa cites Israel's failure to provide food, water, medicine and other essential assistance to Gaza, where Hamas seized power in 2007, two years after Israel ended a 38-year occupation of the enclave.

Hamas official Sami Abu Zuhri told Reuters that the group was following the World Court proceedings with great interest.

"Justice is going to be tested today," he said. "We urge the court to reject all pressure and take a decision to criminalise the Israeli occupation and stop the aggression on Gaza."