Jacinda Ardern arrives at Ratana Pa in first visit by Labour PM since Clark

Prime Minister Jacinda Ardern has arrived at Ratana Pa, fronting on last night's agreement over the revised Trans-Pacific Partnership before the brass band marched her and her entourage to the marae for a powhiri.

Labour and Ratana have an historic alliance going back to the 1930s when prophet Tahupotiki Wiremu Ratana signed an agreement with Michael Joseph Savage.

Ardern is the first Labour Prime Minister to attend the annual celebration of the birthday of Ratana Church founder Tahupotiki Wiremu Ratana since Helen Clark.

This year is the 100th anniversary.

Ardern arrived on a bus with other Labour MPs and the Green Party. Coalition partners NZ First arrived separately, but all three parties were welcomed together as a Government grouping.

National will be welcomed this afternoon, in a break from the past few years when all political parties have been welcomed on in one group.

During the powhiri there was applause when Ratana speaker Andre Mason congratulated Ardern on her pregnancy - followed by a cheeky suggestion she name the baby Waru as a middle name.

"That's a gift from us," he said to laughter.

He said that meant eight and was symbolic for the Ratana centenary celebrations so would be a constant reminder of the alliance.

"I suppose that would seal all the deals we've done over the years between Ratana and Labour."

Mason also acknowledged former Labour leader Andrew Little for his "wisdom and vision" in recognising he should hand over the leadership.

"It took courage to do that. We take the opportunity to greet you and that wise moment of understanding you had last year."

Ardern was given warm applause for her mihi in te reo Maori.

Ardern joked about the name suggestions that had been given for her baby, saying they included Trevor [Mallard], James [Shaw], Grant [Robertson] and Winston and had been suggested by quite a few people to mark the governing arrangement.

She said it had been suggested Winston Peters be godfather. "I pointed out he already was."

In response to a suggestion from Ratana elder Andre Mason for a middle name, Ardern observed when she was shown the Ratana Temple, she was offered a baptism.

"I suspect it was an attempt to baptise the baby early with your chosen name."

On a more serious note, she said she took the alliance with Ratana seriously and saw it as a living commitment, not simply a piece of history.

Prime Minister Jacinda Ardern arrives at Ratana Pa. Photo / Stuart Munro

Ardern spoke of the record number of Maori MPs Labour now had, having won back all the Maori seats.

"With that comes a huge weight of responsibility and expectation which you should hold us to account for. But I can tell you we will hold ourselves to account also."

She said there was still work to do to ensure the vision the prophet Ratana had.

"We will not have met our commitment under the Treaty of Waitangi until we make sure Maori are no longer overrepresented in unemployment statistics, in our prison population, that they no longer have tamariki in poverty and our rangatahi, especially in the regions have every opportunity for a decent job and a decent future."

She said she wanted her Government to be driven by manaakitanga and a model was the response of local Maori after the Christchurch and Kaikoura earthquakes.

"Where there was need, marae opened their doors and responded to people."

She said she promised to listen and understand. "Hold us to account and celebrate with us when we make progress."

Ardern will head to Waitangi next week in the lead-up to Waitangi Day, opting to spend five days in the north rather than the usual two.

Ardern has been granted speaking rights on the marae at Waitangi for the welcome, years after her predecessor Helen Clark was driven to tears because her right to speak was objected to.

It is protocol on many marae for women not to speak.

Ardern said she felt honoured to be offered it. She said she had made it clear that she was happy to follow marae protocol "and whatever decision was made I would happily follow that decision".

She said she had wanted the decision to come from the marae.

The powhiri will be held on the upper marae at the Treaty grounds this year rather than Te Tii after successive tensions at the lower marae around the attendance of politicians and media.

NZ First leader Winston Peters took a pot shot at Gareth Morgan, the former leader of The Opportunities Party who had criticised Peters at Ratana last year.

Peters observed "the cat man" had not made it into Parliament or back to Ratana.

"What's changed is the new government."

He said the new government was aiming at education, health, employment and wages to deliver for Maori.

NZ First MP Shane Jones was given the comedy slot but also had a bit of a serious message.

He took aim at National leader Bill English for his comments that it was not for the Government to ensure the survival of the Maori language, saying it belonged to everybody.

Jones needs land to plant his billion trees on and noted many morehu had suggested a name for Ardern's baby.

"When they offer the name make sure you get the land as well."

A drone above the marae at the start of the powhiri also bothered Jones. He told media if they took a drone to Waitangi "I have no doubt it will be mistaken for a kereru, shot and consumed."

Green Party leader James Shaw spoke during the powhiri, acknowledging the manaakitanga (hospitality) of the Ratana people.

He said his former colleague Metiria Turei was a morehu and pledged to continue with the work on child poverty Turei had championed.

He also referred to Pirimia (Prime Minister) Ardern as "baby mumma" and WInston Peters as the rangatiratanga (chief).

He said it was a great honour to be in government, but also a great responsibility.

"We take our responsibility as ministers to be to hold Te Tiriti o Waitangi central to our work. I wanted to maintain that commitment."

He said the Greens would also pursue the other promises it had made over successive years at Ratana to improvise homelessness, poverty, and the environment.