United Future leader and Ohariu MP Peter Dunne has announced he won't be standing for parliament in the September 23 election.

In a press release issued this afternoon, Peter says he based his decision on ‘recent polling' and a belief there was a mood for change among Ohariu voters.

'This shift in voter sentiment is quite at variance with polling and other data I have seen throughout the year, upon which I had based my earlier decision to seek re-election for a 12th term as MP for Ohariu,” says Peter.

'While I am naturally extremely disappointed after 33 years of service at this apparent change of feeling, I recognise and understand it, and respect absolutely the electorate's prerogative to feel that way.”

Speaking to SunLive, Peter says United Future will continue as a party, but he will not be 'actively involved'.

'I will be stepping down as leader in due course.”

He says he informed Prime Minister Bill English of his decision before stepping down today, but would not comment on what the Prime Minister may have said to him.

The decision to step down means the National Party has lost a potential coalition partner in United Future, which will not return to parliament unless it can secure either another electorate seat, or five per cent of the vote.

National currently has a one-seat majority in parliament.

Peter says he is proud to have worked alongside successive National- and Labour-led governments, and to have served first as an under-secretary and then a minister under seven different prime ministers for just on 15 years.

He adds Ohariu has been a ‘very large part' of his life.

'I have lived continuously in the area for more than 40 years. Jennifer and I raised our family in Ohariu. It is our home. Working for the community and its people over the last 33 years has, at all times, been an absolute delight. I will miss hugely that direct engagement with so many aspects of the life of our community, and I will never forget the huge honour Ohariu gave me by electing me, first as a young 30 year old, and then for the next ten elections after that.”