Officials have been directed to begin working on a declaration of intervention which will be filed, subject to ministerial approval, once South Africa has filed its memorial — which is likely to be a number of months from now.

Tánaiste and foreign affairs ministers Micheál Martin has indicated the intervention will not take a position on whether Israel is committing acts of genocide in Gaza, which was the conclusion of a new UN report earlier this week.

He said: “It is for the court to determine whether genocide is being committed. But I want to be clear in reiterating what I have said many times in the last few months; what we saw on 7 October in Israel, and what we are seeing in Gaza now, represents the blatant violation of international humanitarian law on a mass scale.”

Mr Martin also stressed that third-party interventions at the ICJ are “a complex matter” and “relatively rare”. Ireland has intervened in only one of the four interstate cases initiated under the Genocide Convention since 1948, he pointed out.

“Ireland intervened in one of these — the Ukraine v Russia case — and, after a rigorous and comprehensive process of analysis and consultation over the last six weeks, we have determined that we will do so again in the South Africa v Israel case,” he said.

South Africa has alleged that Israel is breaching the 1948 Genocide Convention through acts and omissions “intended to bring about the destruction of a substantial part of the Palestinian national, racial and ethnical group, that being the part of the Palestinian group in the Gaza Strip”.

The ICJ imposed provisional measures in January, ordering Israel to “take immediate and effective measures to enable the provision of urgently needed basic services and humanitarian aid”. Human rights campaigners have accused the Israeli government of failing to comply with that order.

Israeli prime minister Benjamin Netanyahu denies allegations of genocide and says the IDF “is acting as morally as possible”.