South Africans who join the Israeli military could be prosecuted, the country's foreign ministry said on Monday, as Israel's indiscriminate war on Gaza continued.
The ministry said it was "gravely concerned" by reports that citizens and permanent residents of South Africa had joined or were considering joining the Israeli military.
Anyone wanting to join the Israeli military would have to apply to do so through a cabinet committee, and obtain ministerial approval, according to a statement from the foreign ministry.
"Any person joining the IDF (Israeli military) without the necessary permission of the NCACC is breaking the law and can be prosecuted," read the statement.
Naturalised citizens of South Africa face being stripped of their citizenship, the statement further added.
South African politicians have made similar warnings since 7 October, when Israel launched a war on Gaza that has so far killed almost 20,000 people in the Palestinian territory.
In November, a minister from the presidency said serving for Israel or any other country bar South Africa would be illegal, citing South Africa's Prohibition of Mercenary Activities and Regulation of Certain Activities in Country of Armed Conflict Act.
Black South African leaders and activists in South Africa's civil rights movement have long drawn parallels between their experiences under apartheid and the conditions of Palestinians today. Human rights groups have also accused Israel of practicing apartheid against Palestinians.
In a show of support for Palestine, South African lawmakers voted last month to suspend diplomatic ties with Israel, though the resolution was largely symbolic.
South Africa referred Israel to the International Criminal Court for alleged war crimes in Gaza, also last month. There have also been large pro-Palestine protests in the country since October.
Under the Israeli government's 'Mahal' programme, the military can enlist Jewish people from around the world.
Almost all Western countries have no laws against citizens fighting for Israel, and a significant number of dual Israeli nationals often serve in the Israeli military, either as active soldiers, reservists, or volunteers.