Jacinda Ardern has announced her decision to step down as Prime Minister and Labour leader after five and a half years in the role.

The Prime Minister's unexpected announcement is made during a speech. The 2023 general election will be held on October 14 and her resignation will take effect following the appointment of a new Prime Minister. A caucus vote will be held in three days' time, on January 22.

“Being Prime Minister has been the greatest honour of my life and I want to thank New Zealanders for the enormous privilege of leading the country for the last five and a half years,” Jacinda Ardern said.

She announced there was no special "angle" or "real reason" why she wanted to resign, only that she was "human". Holding back tears, said that she is stepping down after six years of some tough challenges. Now is the time'

Ardern will remain MP for Mt Albert until the end of April to avoid a national by-election. She also said Ardern wanted to spend more time with her family.

Political commentator Ben Thomas said Ardern's announcement was a huge surprise as polls still ranked her as the country’s preferred prime minister even though support for her party had fallen from the stratospheric heights seen during the 2020 election.