Jacinda Ardern exit interview: What her final message to New Zealand will be

Former Prime Minister Jacinda Ardern has ruled out ever returning to politics in New Zealand, revealed her biggest regret, and what she hopes her legacy will be. 

On Wednesday, she'll deliver her valedictory speech and we now know what she'll do next. 

Together the roles can be described as a sort of 'New Zealand Ambassador to the World', and they'll capitalise on her global brand.

Jacinda Ardern has been appointed as Chris Hipkins' Special Envoy for the Christchurch Call - where she'll be continuing the work she started as Prime Minister to counter online terrorist and violent extremist content.

She'll continue rubbing shoulders with royalty, joining the board of Prince William's Earthshot Prize. She described this as like a Nobel Prize for the environment - it is all about finding solutions to the likes of climate change and some of the world's other big environmental problems. It hands out millions of dollars in prize money to help scale these ideas. 

Tuesday was the first time anyone had had a chance to sit down with Adrern since she resigned as Prime Minister, to talk about why she quit, and she was relaxed, energetic and adamant she had made the right call. 

When Newshub met with Ardern, she was packing up 15 years of a life spent serving the public, sifting through the letters and keepsakes, and the extraordinary moments which defined her five years in the Prime Minister's office. That includes a runsheet she had of who needed to be told what when she gave birth.

There's also a jumper she had when she came out of hospital with her new daughter Neve.

It's among a rack of Ardern's clothing destined for Te Papa. Others on that rack include a dress she wore to the Queen's banquet for heads of state while heavily pregnant, the jacket she wore the day she became Labour leader, and the dress she wore when she was sworn in as Prime Minister just months later. 

The packing began ten weeks ago after her shock resignation.

"There are elements of the job I will miss but it was absolutely the right call for me and for New Zealand," Ardern told Newshub.

On Wednesday, she leaves Parliament for good. 

Would she ever consider returning? No, Ardern said.

"This is it for me. This is a full farewell."

Ardern is steadfast in her reason for quitting. She clarified it wasn't burnout, but she lacked the stamina she knew the job needed.

"Yes, I could do the job and I could keep going. But did I have enough in reserve that if another significant event came our way, let alone an election, could I hand on heart say that I was going to be there at 100 percent of my capacity for another three years? I knew casting forward I didn't have that in me."

She also said she didn't quit before she could be voted out.

"If you were afraid of losing, you shouldn't be in politics," Ardern said.

Ardern had become a lightning rod for voters' anger - and knew it.

"But it did occur to me that actually, my departure might just take a bit of heat out. Was it the basis of my decision? No. But I did believe that that might be one of the consequences of it."

On Tuesday, she walked the media gauntlet one last time to her final caucus meeting. 

She wasn't speaking about the politics of the day, but on her achievements and her regrets. 

"I wish we never had a protest on the forecourt of Parliament, I often think about, were there other ways? Could that have been avoided? I don't know the answer, but we wouldn't be human and we wouldn't learn if we didn't reflect on those things. And I still do."

The online vitriol directed at her personally was awful too, with threats dealt with by police against a prime minister reaching an all-time high - but she says that's not the whole story

"I would be deeply saddened if New Zealand's overall view of my time in office was that I was experiencing hatred, misogyny 100 percent of the time. I didn't. Were there moments? Of course… But day to day, my experience was a positive one."

She hopes her legacy will be as a role model for young people and also for her daughter. 

"If I can just simply walk away knowing that there will be kids and girls in particular who think they can do this job just like me and do it with kindness and empathy and compassion then job done."

Would she encourage Neve to get into politics?

Ardern wants Neve to know she can do whatever she wants. 

"She's not the daughter of an ex-Prime Minister. She's Neve. She's her own person. I hope that she has the same experience I hope for all girls in New Zealand, that they don't feel held back by their gender, they feel like they can do anything and they can do it their way. That's all I hope for."

Ardern's first year as PM saw her become only the second world leader to have a baby while in office.

She handed the Prime Ministership to Winston Peters, and returned after just six weeks.

"I was very conscious that I'd been elected to do a job and I needed to do that job."

She's someone who likes to preserve history, like the first United Nations pass made for a baby and handwritten notes of national significance. 

Her empathy and leadership through the crisis and the gun reform that followed was met with international acclaim.

"I remember feeling so angry that this individual had thought that they could come over and try and attack a part of our community and other them."

It's why - in her next role - she's committed to continuing her work on the Christchurch Call. 

"I still feel a duty at a personal level to the community who were affected by March 15."

It's a role she asked for and will not be paid for. 

"Things have fundamentally changed because of the Christchurch Call, you will not experience what could have occurred before March 15 because of the Christchurch Call, but there's more work to be done."

There's more work to be done on climate change too which is why she's taken a role on the board of Prince William's Earthshot Prize.

"Prince William and I spoke about his plan and dream for this before it had a name. So to be able to come back full circle and support his work alongside an amazing board, I feel very lucky."

But for now it's time to finish packing, say goodbye and do one more thing.  

She has her valedictory statement on Wednesday. 

Asked what her final message is for New Zealanders, an emotional Ardern said: "Thank you".