The case will be the first of its kind since Hamas, the Palestinian militant group in charge of the Gaza Strip, launched a deadly assault on Israeli soil on 7 October.
The attack killed around 1,200 people with 240 more taken hostage, around half of whom have been subsequently released.
Israel’s response, including a heavy bombing campaign across the enclave and a three-pronged ground offensive, has killed at least 23,000 Palestinians, according to the local Hamas-run authorities, and displaced more than 85 percent of the population.
Below we look at the case being made by South Africa and what it means for Israel.
What is genocide?
Under international law, genocide is defined as committing acts with the intention of destroying, in whole or in part, a national, ethnic, racial or religious group.
Those acts include: killing or causing serious bodily or mental harm to members of the group; deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part; imposing measures intended to prevent births within the group; or forcibly transferring children of the group to another group.
While the destruction of Hamas – the stated aim of the Israeli military – would not come under the jurisdiction of genocide, the deliberate killing of Palestinians, if proved, would be considered under the terms of the crime.
What is the case against Israel?
South Africa has submitted evidence claiming they show “acts and omissions” by Israel that “are genocidal in character because they are intended to bring about the destruction of a substantial part of the Palestinian national, racial and ethnic group”.
This refers both to Israel’s active bombing of the Gaza Strip and its alleged failure to prevent harm to civilians.
Their case also highlights public comments made by Israeli officials, including from Prime Minister Benjamin Netanyahu, as proof of “genocidal intent”.
Former UK opposition leader Jeremy Corbyn announced on Tuesday that he was joining the South African delegation fighting the case.
What has Israel said about the case?
Israel has strongly rejected the allegations, calling them “baseless”.
Mr Netanyahu said about the accusations: “No, South Africa, it is not we who have come to perpetrate genocide, it is Hamas. It would murder all of us if it could.” He and the Israeli military have said they are acting as morally as possible.
The military says they have airdropped flyers warning of imminent attacks, called civilians’ phones to urge them to leave targeted buildings, aborted some strikes when civilians were in the way and repeatedly stated that it distinguishes between Hamas and the Palestinian people.
Who is hearing South Africa’s case?
The International Court of Justice (ICJ), the United Nations’s top court, will hear the case.
Based in the Hague, the Netherlands, the court was established after World War Two to settle disputes between states and give advisory opinions on legal matters, which is what it is being asked to do with Israel.
It is not the same as the International Criminal Court (ICC), which can prosecute individuals for crimes of genocide. In March last year, for example, the ICC charged Vladimir Putin and Maria Lvova-Belova, the Russian children’s ombudsman, with genocide for the abduction of Ukrainian children.
The ICJ does not hold such power. However, its opinions carry weight with the UN and other international institutions.
Can the court make Israel stop the war in Gaza?
South Africa wants the ICJ to order Israel to “immediately suspend its military operations in and against Gaza”.
Given the limitations of the ICJ and Israel’s conviction in its war against Hamas, it is highly unlikely any request made by the court will be heeded.
Rulings are theoretically legally binding on parties to the ICJ – which include Israel and South Africa – but in practice, they are unenforceable.
In 2022, the ICJ ordered Russia to “immediately suspend military operations” in Ukraine, for example, but the order was ignored.
When will the ICJ make a decision?
The first stages of the hearing will begin on 11 January.
While the ICJ could rule quickly on South Africa’s request for Israel to suspend its military campaign in the Gaza Strip, a final ruling on whether Israel is committing genocide could take years.
Why has South Africa brought the case?
As a signatory to the UN’s 1948 Genocide Convention, South Africa says it is obliged to launch this case against Israel.