Green Party MP Jeanette Fitzsimons confirmed today she had resigned from Parliament with her efforts praised by Prime Minister John Key.
Ms Fitzsimons, the former co-leader, said it was time for a change of pace after a 13 year parliamentary career.
"It's been a huge privilege to lead the Greens in the New Zealand Parliament for the last 13 years and I have both loved it and hated it, but it's the right time now for me to go. It's the right time for me and the Greens," she told a press conference today.
She is the second Green MP to quit Parliament this term; Sue Bradford resigned after losing out to Metiria Turei in a battle over who should replace Ms Fitzsimons in the leadership, after she decided to step down last year.
Ms Fitzsimons, who celebrated her 65th birthday earlier this month, said she wanted to spend more time on the farm and with her grand children.
Prime Minister John Key hailed Ms Fitzsimons this morning, saying she was an honest person with humility.
"She has had very core values and beliefs," he said.
With the late Rod Donald she made the Greens a formidable force. "She will be missed in parliament."
She put across her point of view but was never nasty or antagonistic. "Jeanette always plays the issue, and never the person," Mr Key said.
"She has very strong views, and she's not going to back down and no one will die wondering what Jeanette thinks when it comes to the environment."
Labour leader Phil Goff said Ms Fitzsimons was a good person and a good politician.
"We didn't always agree but she is a loss to Parliament."
Ms Fitzsimons, was the first Green MP to speak in Parliament following the 1996 election and is believed by the party to be the first Green candidate in the world to win an electorate in a first past the post contest, when she won the Coromandel seat in 1999. She lost the seat the following election to National.
In 1998 Ms Fitzsimons introduced the Energy Efficiency and Conservation Act and spearheaded Green party negotiations for a household insulation fund.
She shared the co-leadership with the late Rod Donald, who died just weeks after the 2005 election.
Ms Fitzsimons will be replaced by 28-year-old environmental advocate Gareth Hughes, who plans to move from Auckland to Wellington.
Mr Hughes had been working for Greenpeace where he coordinated the Sign On campaign gathering support for climate change policies.
Ms Fitzsimons wrote to Speaker Lockwood Smith this morning to say she will finish as an MP on February 11.
Russel Norman, who succeeded Mr Donald as co-leader, said the party had appreciated that she had stayed on after Mr Donald's death.
"Jeanette has played a critical role in leading the Green Party through the first phase of our history and has mentored and supported a new wave of Green MPs and co-leaders."
Ms Turei said she would be missed.
"We will have a very new team shortly in Parliament and that team is standing on the shoulders of Jeanette and Rod and Sue and all of those who first came in in 1999."
- with NZPA and MICHAEL FIELD
Will you be voting in this year's General Election?Related story: Map: Voter enrolment rates declining