THE HAGUE - A legal hearing into the war in Gaza opens in The Hague on Thursday as the international court of justice (ICJ) hears arguments alleging that Israel is committing genocide in the territory.

South Africa, which has brought the case, is asking the UN court to act urgently “to protect against further, severe and irreparable harm to the rights of the Palestinian people under the genocide convention, which continues to be violated with impunity”.

It comes as the assault on Gaza – launched in response to the 7 October attacks on Israel by Hamas in which militants killed 1,200 people, mainly civilians, and took 240 people hostage – continues to wreak a devastating toll.

Since the 7 October attacks, Israel has killed more than 23,000 Palestinians in Gaza, according to Gaza’s health ministry, about 70% of whom are believed to be women or children. The UN’s Palestinian relief agency, UNRWA, has estimated that 1.9 million people have been internally displaced by the war in Gaza – nearly 85% of the population – while tens of thousands of buildings have been destroyed.

In its 84-page written application to the ICJ to open proceedings, South Africa said: “The acts and omissions by Israel complained of by South Africa are genocidal in character because they are intended to bring about the destruction of a substantial part of the Palestinian national, racial and ethnical group.”

Genocide cases, which are notoriously hard to prove, can take years to resolve, but South Africa is asking the court to speedily implement “provisional measures” and “order Israel to cease killing and causing serious mental and bodily harm to Palestinian people in Gaza”. The filing also says Israel should cease deliberately inflicting conditions calculated to bring about the destruction of the Palestinians as a group, be ordered to prevent and punish incitement to genocide, and halt restrictions on aid as well as evacuation directives.

Israel reacted furiously when the application was made, calling it “baseless” and a “blood libel”. It says it is acting in self-defence, to protect Israelis by destroying Hamas. The country’s biggest supporter, the US, has dismissed the case as “meritless”.

Ahead of the case, Israeli prime minister Benjamin Netanyahu posted a video clip saying Israel was fighting Hamas, not the Palestinian population, and was acting in full compliance with international law. “Israel has no intention of permanently occupying Gaza or displacing its civilian population,” he said.

Outside the court, both sides will also attempt to win the battle of public opinion. Israel is holding a series of events in The Hague, including a peace march on Thursday morning as South Africa prepares to state its case, exhibitions about the Israeli hostages still held by Hamas, and interviews with the relatives of hostages.

South Africa said on Wednesday that its delegation will include the former UK Labour party leader Jeremy Corbyn, who is a longtime supporter of the Palestinian cause but whose time as opposition leader was marred by antisemitism allegations.

South Africa’s ruling African National Congress (ANC) party has a long history of comparing Israel’s treatment of Palestinians with that of black South Africans under apartheid.

The Organisation of Islamic Cooperation, which has 57 member states, has welcomed South Africa bringing the case, while individual countries have also expressed support. Belgium’s deputy prime minister, Petra De Sutter, tweeted that she wanted her country “to take action at the International Court of Justice, following the lead of South Africa”.

Both sides’ legal teams will have the same time to make their case – approximately three hours – with South Africa going first on Thursday and then Israel responding on Friday. Judgment will be reserved until a later date, but could come within weeks.

The genocide convention, drawn up in 1948 after the second world war and the murder of 6 million Jews in the Holocaust, describes the crime as “acts committed with intent to destroy, in whole, or in part, a national, ethnical, racial or religious group”. The acts include killing members of the group or causing them serious bodily or mental harm,

The Hague cannot enforce its decisions and it is possible that Israel could ignore an adverse judgment, but that would only fuel further international condemnation of its military campaign.