Independent Chris Carter has given his final speech in Parliament as he leaves politics to take up a role with the United Nations in Afghanistan.
The MP for Te Atatu was kicked out of the Labour Party last year after his botched attempt to destablise the leadership of Phil Goff.
His retirement will not force a by-election, as it comes less than six months before the general election on 26 November.
Mr Carter told Parliament on Tuesday that the last year had not been easy, but now is the time to look forward - not back.
"I am, and will always be, a Labour person. I still consider myself a Labour MP and I still believe passionately in social democracy and that the Labour Party has the best philosophy for ensuring social justice and providing effective pathways to realising individual potential."
Phil Goff said Mr Carter can be proud of the work done in the past as a local MP and a minister in the previous Labour-led government and wished him well in his new job.
However, Mr Goff said Mr Carter also got some things grievously wrong and his expulsion from the party was sadly the end of his political career.