In grief, Maori consider their next monarch

Tuheitia died after complications from heart surgery, aged 69.

King Charles sent condolences, saying he was 'profoundly saddened' by the death of King Tuheitia. (David Rowland/AAP PHOTOS)

Clad in black, and with many wearing wreaths of kawakawa leaves as a traditional sign of grief, Maori tribes from across New Zealand have led delegations onto the marae (or meeting house) as part of a week-long farewell.

Leaders have regaled with traditional oratory, waiata (or song) and haka in honour of the fallen monarch.

That will continue on Tuesday and Wednesday before the formal tangihanga (or funeral) takes place on Thursday.

The last tangihanga for a fallen monarch, Te Atairangikaahu in 2006, drew more than 100,000 visitors, with 10 per cent of the country watching the broadcast.

Alongside mourning, leaders of tribes aligned with the Kiingitanga movement are now considering a successor for the elected, rather than hereditary monarchy.

TVNZ political editor Maiki Sherman said the process would happen "behind closed doors between an advisory council made up of Maori leaders from across the country".

The office of the Kiingitanga has asked New Zealanders to refrain from speculating on who it might be out of respect.

Just seven have held the role dating back to 1858, when it was created to unify Maori, excluded from parliament, during a wave of European settlement.

The transition of power comes at a critical moment for New Zealand, where a new centre-right government is re-fashioning its relationship with Maori and even threatening to cut Maori out of constitutional arrangements.

Historian Vincent O'Malley said Tuheitia led in the spirit of the 1850s, and represented Maori "endurance and survival".

"Tuhietia will be remembered as a man of quiet humility and strength and also a forceful advocate for Maori interests and for unity," he told AAP.

In January, when the government's Maori policies became clear, Tuheitia convened a national hui (or gathering) for unity, drawing around 10,000.

At a time when many were calling for fierce protests, Tuheitia's prescription was simply: "Just be Maori".

"The best protest we can make right now is being Maori. Be who we are. Live our values. Speak our reo (language)," he said.

"Be Maori all day, every day. We are here. We are strong."

Dr O'Malley said Tuheitia's leadership was powerful.

"Tuheiria was instrumental in bringing Maori together to debate and consider how to respond," he said.

"The challenges that are confronting Maori at the moment are huge ... all sorts of government initiatives and proposals that for many Maori feel they're under siege from the government."

Despite his role, Prime Minister Chris Luxon - who will miss the tangihanga while on a trade mission in South Korea - enjoyed warm personal relations with Tuheitia.

New Zealand Prime Minister Chris Luxon established a good personal relationship with the Maori king. (Ben McKay/AAP PHOTOS)

Mr Luxon spoke at the marae on Saturday, showing emotion as he spoke, his voice cracking.

"I was also thinking of the family, they've lost a husband, they've lost a dad. Not just a king, but they've lost a family member as well," he told journalists.

Mr Luxon recalled Tuheitia's comments at the 18th anniversary of his coronation earlier in August.

"Just a week ago at this very place you said, 'we need to focus on getting in the waka (canoe) and working together'," he said.

"You said growing together is crucial, we've come a long way as a country and we can go even further."

Along with Maori tribes and Kiwi leaders, Cook Islands Prime Minister Mark Brown have been among dignitaries to pay their respects, with more expected from across the Pacific.

Jemaima Tiatia-Siau, Pacific Studies Professor at the University of Auckland said there was "immense respect" for Tuheitia across the region.

"Kiingi Tuheitia was a galvanising force, despite his humble background, his mana and the mana of the Kingitanga emanated far beyond Aotearoa," she said.