"The best thing I can do is create a space for change to happen."
He said he would stay as Minister until the election, but did expect to relinquish some of those responsibilities to his successor to allow him to have the mana of the role before the election.
He would also stay as a supporter and a leader within the party.
He made his decision with a "heavy heart."
"We are totally committed to the concept of having a large group of Maori within Parliament who are led by kaupapa Maori."
He said he had spoken to Prime Minister John Key who was saddened by his decision, but supportive of him.
He said the party had not created personal conflict between the MPs.
Dr Sharples told the Herald of his decision yesterday, saying the uncertainty over the leadership was taking too much of a toll on the party and had given a perception of disunity.
He made the public announcement this morning, with co-leader Tariana Turia and Te Ururoa Flavell, who challenged Dr Sharples for his role in January, by his side.
Mr Flavell is likely to replace Dr Sharples after the Maori Party's conference in a fortnight.
Mrs Turia announced last year that she would retire from politics in 2014 and had suggested Dr Sharples follow her lead so the party could get its succession in place.
However, the two retirements have cast doubt on whether the Maori Party will be able to rebuild, given it is under fire for its relationship with National.
Mr Flavell refused to say whether he now expected to be made the leader, saying that was a decision for the Maori Party council at its AGM.
Mrs Turia said she believed it was the right decision, although it was Dr Sharples' decision to make.
"The majority of our people are under 35 years of age. We believe we need that voice to come through."
She said although they had taken a different view on the leadership, they had always been united.
She said talk that it was the end of the Maori Party was simply "politicking." She said Labour had lost more than 50 per cent of its vote in Ikaroa-Rawhiti while the Maori Party had held up its 2011 support.
She said Maori people needed to consider what they wanted.
"Our people need to decide whether they want to continue living a life of activism standing on the sidelines, or someone actually progressing their issues. That's what the Maori Party stand for."
Dr Sharples said he was not pushed into making his decision, but had believed it was in the best interests of the party.
Asked how it would affect the party's electoral chances, co-leader Tariana Turia said "What we've got to do is work hard to restore their faith to show that the progress made will continue. We have to stop believing it is individuals that make the difference. It is the kaupapa."
- Claire Trevett of the NZ Herald
