A Ngāi Tahu leader has called for a rethink on a movement to change New Zealand's official name to Aotearoa, saying it risks overlooking the South Island. 

A name change has been brought to the fore by the Māori Party, which launched a petition calling for restoring Māori names for the country, as well as for towns, cities and other places. 

Otakou marae kaumatua Edward Ellison said while he agreed with the Māori Party's initiative in principle, it would be "a rash move to rush forward in a change of that substance and nature". 

At the core of his reservations is the history of the name Aotearoa, which many people did not realise originally referred solely to the North Island. 

He had been heartened to see Aotearoa catch on in an informal sense over the years, but was reticent about a more formal arrangement. 

"I'm really proud of it to see it on our passports and other licences, but it's another quantum leap to adopt a name that's grown on us through osmosis, as opposed to a really significant decision to change the name of the country." 

Ellison said a more commonly used title in the south was Aotearoa me Te Waipounamu, which encompassed both major land masses. 

If a name change was on the cards, a more thorough discussion would be needed to ensure an inclusive name was selected. 

"Otherwise we feel sort of forgotten about, and it's just another form of, at the worst, say colonisation." 

However, he gave the Māori Party "full marks" for bringing the subject into the national consciousness. 

"That's partly what their role is, to shock the people into thinking about these things." 

On the wider subject of changing the names of settlements and natural features, he said Ngāi Tahu had their own process to do similar work in the South, which was more gradual than what the Māori Party suggested. 

He was not sure at the national level whether it was a better option to change names sooner by legislation or allow them to evolve over time, but was happy with their local process. 

"It's a bit slower, but they do it when the people are ready." 

- Andrew Marshall, ODT