Prime Minister John Key confirms he will attend Waitangi, but says it's possible protesters could block him from going on Te Tii Marae.

Prime Minister John Key has confirmed he will attend and speak at Waitangi - but says it is possible protesters could physically block him from Te Tii Marae.

Key's attendance at the annual celebrations had been up in the air, after Northland iwi leaders were divided on whether he should be blocked due to his handling of the Trans Pacific Partnership Agreement, which some Maori leaders strongly oppose.

A vote was called for at a meeting on Tuesday afternoon and leaders voted 38-14 in favour of stopping Key attending, but was overruled by Ngapuhi elders.

CHRIS SKELTON/FAIRFAX NZ Prime Minister John Key vowed to return the Government to Waitangi but now he is turning his back on Northland.

Key said marae trustees had issued him a formal invitation after another meeting on Tuesday night, with "all of the same privileges and procedures there've been in the past", and he would attend the event.

READ MORE:

* Treaty of Waitangi quiz

* More fur flies at Waitangi

* John Key welcome at Te Tii Marae but if he can't speak he won't attend

* Peaceful beginning to Waitangi

* Jostling continues as Key escorted onto Te Tii marae

However, the large crowds of protesters expected at Waitangi were a complication, with the possibility that it could be too unsafe for him to get onto the marae.

JOHN SELKIRK/FAIRFAX NZ A mud splattered Don Brash, then leader of the Opposition, talks to media after being hit by mud at the gates of Te Tii marae at Waitangi in 2004.

"In a practical sense, if there's so many people that they physically block the cars from getting in, I can just envisage a situation where I don't actually get on the lower marae."

Key said he and other government attendees would "do everything we practically can to go", but did not rule out staying off the marae if it was a security risk.

"I can't put a whole lot of people in a situation where they could be endangered - it's not fair on them and actually it's a responsibility I don't want to take, but I'll do the very best I can to get there."

He was "not looking for an excuse to get out", and said he was happy to defend the Government's support for the TPPA deal at Waitangi.

Key ruled out speaking in a tent away from the marae, as had been suggested by some Maori figures including former MP Hone Harawira.

"I'm not going to speak in other parts of the marae...I don't think that would practically work, and secondly there's a lot of other commitments on my time."

WAITANGI DIVISIONS

It was Titewhai Harawira, who has escorted Prime Ministers onto the marae for many years, along with Ngapuhi co-chairman Rudy Taylor and other leaders, who agreed to the vote going ahead despite their support for Key at the marae.

When the vote went against Key they were left with no choice but to veto it, which has caused division amongst trustees with some saying Key won't be welcome to speak if he turns up.

Harawira's son, Hone, a former MP and opposer of the TPPA, abstained from voting but said his mother and other leaders had "put themselves in a situation of real jeopardy" by allowing the vote in the first place.

"It's a national marae and Ngapuhi are the guardians of it. What they should have done is asked other leaders from other areas for their opinion, listened to them and then decided. They didn't have to take a vote.

"They handled the whole thing really badly," he said.

Labour Maori Affairs spokesman Kelvin Davis, who was also at the meeting, said tikanga (custom) dictates that Key should be invited onto the marae so the trustees were right to overrule the vote.

On Tuesday, Key said he had made a commitment to go to Waitangi but he wouldn't "gate-crash" and he wouldn't attend if he wasn't able to speak.

"I"m not going if I can't speak, it's pretty simple."

He said Te Tii was the gateway to the Waitangi treaty grounds and he wouldn't attend at all if he wasn't welcome at the lower marae.