Ill-health has forced King Tuheitia to stand down from public-speaking arrangements and choose his eldest son to represent him in the immediate future.
A King's Council will also be established to advise the son, Whatumoana Te Aa Paki.
Iwi leaders and members of the kahui ariki (royal family) met at Turangawaewae House, Ngaruawahia, yesterday where King Tuheitia, who is 58, told them that Te Kaunihera a te Kiingi (the King's Council) had been established, and his elder son would represent him until his health improves.
A statement from the King's office said his ill-health was affecting his ability to carry out his official duties.
Waikato Tainui tribal heavyweight and former MP Tukoroirangi Morgan, who was appointed a member of the King's Council, said iwi leaders endorsed Whatumoana filling in in his father's absence.
He said it was a "very pragmatic solution" as the King sought medical treatment.
"This is certainly not about succession," he said.
"His son will represent him at the various hui that are called and require his attendance."
Also appointed to the council is Te Rangihiroa Whakaruru, the King's private secretary, who had his firearms licence revoked after a domestic incident at his fiancee's house last September.
Mr Whakaruru gained notoriety when he had to pull out of an anti-domestic abuse campaign after his stepdaughter revealed he had beaten her and her mother. He later admitted the allegations.
Other council members include George Mahuta, Sir John Goulter, Rahui Papa, Tania Simpson and Hukiterangi Muru.
In 1903, when Kingi Mahuta took up a seat in the Legislative Council in Wellington, his younger brother, Te Wherowhero Taawhiao, performed his Kingitanga duties.
He also took the title Te Whirinaki a Kiingi Mahuta.