Embattled Labour Party leader David Shearer has stood down.
At this stage no new leader has been elected yet.
The announcement came at a hastily arrange press conference.
There was no early indication of what exactly had prompted the move from Shearer, though it was hardly unexpected given the way the party has failed to fire in the opinion polls.
In announcing his departure Shearer said there had been "no ultimatum" and "no vote".
"But from the soundings I have taken from colleagues I realise I no longer enjoy the confidence of a number of my caucus colleagues."
Shearer said he had been "privileged" to lead the Labour team for the past 20 months and "I’m proud of the gains we have made in that time".
But the party needed to do more, so the time had come to hand over to a new leader to take the party through to the next election in 2014, he said.
"It has been a challenging time off the back of the 2011 election result.
"We have rebuilt and reformed the party and under my leadership, we have released a number of significant policies to improve peoples’ lives.
“KiwiBuild – which will put 100,000 families into their first, affordable home. NZ Power – which will bring down power bills for every Kiwi family and business. And there is much more to come."
Shearer said that after spending the last 20 years of his life leading humanitarian and reconstruction projects overseas, he came home to New Zealand because he is passionate about this country.
"We have a history to be proud of but I believe our best years lie in front of us. But to really take this country forward, we need a change of Government. We need a progressive Government with fresh ideas.
"We need a Labour-led Government.
"The ambitions of one person should never be larger than that greater purpose. It is time for someone else to take up the challenge of leader.
"I came into politics to make a difference. I believe I have done that. And I will continue to do so as a loyal member of the Labour team and the MP for Mt Albert.
"I would like to thank my fellow MPs and my staff for all their hard work. I wish them all the best for the future."