President Cyril Ramaphosa has declared a special official funeral category 1 for the late KwaZulu-Natal King Goodwill Zwelithini.
News24 reported on Friday that Zwelithini had died in hospital after he had been ill for about a month.
There were concerns about the blood sugar levels of the 72-year-old and he received treatment in the ICU when he became unstable.
Tributes have been pouring in since the news of the king's death on Friday morning.
Ramaphosa has authorised that the National Flag be flown at half-mast at every flag station in the country from Saturday, until the evening of the funeral date.
In a statement, the presidency said the funeral would entail ceremonial elements provided by the South African National Defence Force. "In terms of Chapter 1.5.2(a) of the State, Official and Provincial Funeral Policy Manual, the President may designate the funeral of a distinguished person as a Special Official Funeral.
"President Ramaphosa has expressed his sincere condolences to the Royal Family, to the Zulu nation, and to the people of KwaZulu-Natal and beyond – for whom the Ingonyama was an important symbol of history, culture and heritage."
Details of Zwelithini's funeral would be announced in due course, the presidency said.