Labour's deputy leader Annette King is retiring - and she and Leader Andrew Little are backing Jacinda Ardern as her replacement.
"After some reflection, I have decided to step down from the deputy leader's position in the Labour Party," Ms King announced on Wednesday morning.
Ms King is a long-serving MP for Rongotai, and Labour's health spokesperson. She told Newshub "there has been absolutely no pressure on me to stand aside at all".
"I've been around 30 years in politics. Ten elections, eight leaders, and one thing I really wanted to achieve before I did retire was to ensure my successor was confirmed in the seat of Rongotai, and that's Paul Eagle."
Mr Eagle was confirmed two weeks ago.
She is nominating newly-elected MP for Mt Albert Jacinda Ardern as her replacement.
"I actually think that Jacinda is ready to be the deputy. Having that win in Mt Albert - having a base - being grounded in an electorate is really important. And she has worked hard, she's stood in seats that are unwinnable, and she's won, and she's ready, and I think she'll make a really good deputy."
She said Ms Ardern is going to be "one of the stars of the future".
Leader Andrew Little is also throwing his support behind Ms Ardern.
"She has performed extremely well as a list MP and her resounding win in the Mt Albert by-election is further proof that she has what it takes to be my deputy."
After she romped home with a landslide victory of 77 percent of the vote in the Mt Albert by-election at the weekend, Ms Ardern was ardent in not talking about the leadership.
"I have aspirations, but it's not about relative position in caucus," she told AM Show host Duncan Garner on Monday.
"I wouldn't mind five minutes just being the MP for Mt Albert."
Mr English wished Ms King well.
"I think they'll really miss her. Annette's been a long time, reasonable, stabilising influence and broadly respected across the Parliament".
"It'll be a bit of challenge for the Labour Party I think. We certainly wish Annette well…there'll be a big gap in the Labour Party".
However Mr English said he's not worried about Labour fresh look in an election year - and said that Ms Ardern is "untested".
Ms Ardern hit back at Bill English. "He's been tested as trying to become Prime Minister before and that didn't work out so well for him," she said.
"So maybe coming in fresh and new into the role will be a good challenge for me but one I'm ready for."
Mr Little wouldn't comment on what previous conservations he'd had with Ms King about the leadership.
"She knows her own mind, she's made her own decision".
Ms Ardern is also the party's spokeswoman for Justice, Arts, Culture and Heritage, Children, and Small Business.
Ms King was born in Tasman and entered politics in 1984, elected to office in the Horowhenua seat.
By 1989 she was promoted to Minister of Employment and Youth Affairs, and the following year, Minister of Immigration.
After spending six years as an MP holding various ministerial portfolios, she lost her seat and her place in Parliament and took a three year hiatus.
She returned in 1996, elected in the newly-established Rongotai electorate.
Over the course of Helen Clark's Government she held a number of portfolios, and after Labour lost the 2008 election she became deputy leader.
Labour will vote for their new deputy leader next Tuesday.