Pallade Veneta - Jacinda Ardern delivers final speech to New Zealand parliament

Ardern shocked New Zealand earlier this year when she announced she was stepping down as prime minister and retiring from politics, saying she no longer had "enough in the tank".

Draped in a korowai -- a traditional Maori feather cloak -- Ardern recalled her humble beginnings in a working class family, and how she never expected to lead the country.

"It was a cross between a sense of duty to steer a moving freight train... and being hit by one," she quipped during her valedictory address.

"And that's probably because my internal reluctance to lead was matched only by a huge sense of responsibility."

Ardern steered New Zealand through natural disasters, the Covid-19 pandemic and the 2019 Christchurch mosque massacre -- in which a white supremacist gunman killed 51 Muslim worshippers.

But she singled out the climate crisis as the defining issue of her time in politics.

"Climate change is a crisis. It is upon us," she said.

"And so one of the very few things I will ask of this house on my departure is that you please take the politics out of climate change."

- Horrific grief -

The 42-year-old, once the youngest woman leader in the world, choked up at several points during the speech, which she started and finished in the Maori language.

Her voice was thick with emotion as she recalled the pain caused by the Christchurch attack, which she said had left her "bereft".

"Having sadly seen our nation in horrific moments of grief, I've concluded that countries don't move on from tragedy, rather they become part of your psyche," she said.

Ardern ended her speech by saying she hoped she had shown that being tough and ruthless were not the only hallmarks of good leadership.

"I cannot determine what will define my time in this place," she said.

"But I do hope I've demonstrated something else entirely -- that you can be anxious, sensitive, kind and wear your heart on your sleeve."

Ardern left the debating chamber to thunderous applause and a standing ovation, before colleagues and opponents alike broke out into a series of Maori folk songs.

She will now devote herself to stamping out online extremism as part of the Christchurch Call project, which she set up as prime minister in the wake of the mosque attack.

- Lightning rod -

French President Emmanuel Macron, who took part in the first Christchurch Call summit, said he was reassured to see Ardern continuing to "fight terrorist and violent extremist content online".

Ardern will also become a trustee of Prince William's Earthshot Prize, which hunts for solutions to the planet's most urgent environmental challenges.

Despite her glittering reputation on the international stage -- she graced the cover of Time Magazine in 2020 -- Ardern was far from universally adored at home.

She became a lightning rod for online abuse as her premiership wore on, and was regularly targeted in social media posts filled with violent and sexist language.

A recent study by the University of Auckland found Ardern was targeted by 50 times more abuse online than any other high-profile figure in New Zealand.

Earlier this year, a New Zealand man was sentenced to spend more than a year in prison after threatening to kill her.

But Ardern has been reluctant to blame such attacks for her resignation, instead emphasising the desire to spend more time with her fiance, Clarke Gayford, and her young daughter, Neve.

S.Urciuoli--PV