Former National prime minister Jim Bolger has offered insight into the opportunities on the world stage Jacinda Ardern will be presented with after her resignation - but he was adamant none will rival the stress of being PM.

Bolger, now 87, was prime minister from 1990 to 1997 and said Ardern will definitely be approached with offers similar to what he received, including ambassadorships and chairing international companies.

The 42-year-old Ardern would be particularly in demand because of her international profile as a young female leader, Bolger said.

“She’s had a high public profile for a young woman who’s become Prime Minister. She’s a young person. Clearly there’ll be other opportunities that she may wish to take up,” Bolger said.

 “I of course went as ambassador to Washington for nearly four years and then I did a number of things like chair an international agricultural forum. I helped set up KiwiBank. I managed that for a number of years. I chaired a number of companies, still do. So they’ll be tasks for her, there’s no question about that.”

Bolger also noted he was a member of the InterAction Council, which is made up of former world leaders including former US President Bill Clinton, former UK prime minister John Major and former Russian prime minister Viktor Zubkov.

The council meets and produces an annual report reflecting and advising on the “structural factors driving the global agenda” and covering such topics as development, environment and population.

Bolger said the InterAction Council will also have its sights on Ardern.

 “They’ll want to put Prime Minister Jacinda Ardern into their lineup, there’s no question on that.”

Ardern has also been touted as having a potential future in the United Nations after several appearances and speeches at the General Assembly - including making history in New York in 2018 by being the first world leader to attend the assembly with her newborn baby, Neve.

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Her latest speech at the UN was also in New York in September in which she condemned Russia’s war in Ukraine and called for a ban on nuclear weapons.

Leaders around the world have responded to Prime Minister Jacinda Ardern's announcement she will stand down on February 7. Photo / Warren Buckland

Ardern announced her resignation, by no later than February 7, at the Labour retreat in Napier today, and was asked if a role at the UN was on her radar after New Zealand politics.

“That [UN] has not been my focus. My focus has been this decision, supporting the Labour team through this next stage. Beyond that, I have no plans other than spending a bit of time with my family and then seeing what’s next. But that [UN] hasn’t been my focus.”

Pressed on whether Ardern held ambitions for the UN eventually - rather than a direct focus now - she again denied any plans.

“That has never been my focus, and that hasn’t been my ambition. I haven’t been here for that purpose. I’ve been here to serve New Zealand. I’ll then take each day as it comes,” she said.

Another former Labour prime minister, Helen Clark, was the administrator of the UN Development programme from 2009 to 2017 and challenged for the top Secretary-General role in 2016.

But despite speculation around Ardern’s possible future at the UN, Bolger said none of the post-PM roles he held compared to the stress of leading New Zealand.

“Clearly they’re not [as demanding]. Even though setting up KiwiBank was controversial because my old party didn’t want it at all. I thought it was a good idea and could make it work, and did. So it just depends on the job you have, the position offered,” Bolger said.

The former National leader was also somewhat bemused that Ardern had bowed out of the top job after five years, given her young age.

“This is a short Prime Ministership for stepping down,” he said.

“But I still am surprised that after five years and a little bit that it’s got too much. I’m sympathetic, but I’m surprised. I’m just stating the fact.”

Meanwhile, former Prime Minister Helen Clark said Ardern had faced an unprecedented level of “hatred and vitriol”.

“It was with deep sadness that I received the news on waking in Europe this morning that Prime Minister Jacinda Ardern is stepping down.”

Clark said Ardern had done an extraordinary job in leading New Zealand through major crises, “delivering on a large social policy agenda aimed at rebuilding opportunity and fairness, presiding over an economy which has performed better than most of its peers in challenging global circumstances, and positioning New Zealand as a country which stands for international co-operation and decent values”.

“The pressures on Prime Ministers are always great, but in this era of social media, clickbait and 24/7 media cycles, Jacinda has faced a level of hatred and vitriol which, in my experience, is unprecedented in our country. Our society could now usefully reflect on whether it wants to continue to tolerate the excessive polarisation which is making politics an increasingly unattractive calling.

“Much will be written about Jacinda’s substantial and significant legacy. For now, I express my gratitude to Jacinda for the humanity and empathy she brought to leadership, and wish her and her family well for the next chapters of their lives.”