Vernon Tava wants his new party to "always be in Government" regardless of who's leading it.
Mr Tava, who's previously challenged for the Green Party leadership and stood to be a candidate for National, is setting up a new vehicle for his political ambitions - the Sustainable NZ Party.
"It's not easy setting up a political party, I've discovered," he told The AM Show on Monday. "It's a challenge, it's a hill to climb."
This week he'll be sending out membership forms to those who've registered an interest in joining, and is confident the party will reach the 500 paid-up members to be registered with the Electoral Commission. But he won't say who's among them just yet.
"There are a lot of really high-calibre people who are keen to be involved and are coming forward, we've got to drip-feed those out to keep everybody excited over time."
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Like the Opportunities Party, Gareth Morgan's ultimately unsuccessful attempt to get into Parliament, Mr Tava says he'll be happy to work with both sides - and rejects suggestions it's a "blue-green" party which would be happier to work with National.
"I don't know about blue-green. It's a party that is neither left nor right - it could work with Labour or National or anyone else who's in a position to form a Government."
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Asked who he'd side with right now, based on their current policies, Mr Tava declined to answer.
"Ultimately the voters decide. The first party you go to is the one that has the most number of votes. That's the one that has the clearest mandate from the public - they're the ones you start talking to.
"I think we've seen the error that comes from pre-committing to one party or the other. That's the position the Greens have put themselves in… you're limited in your ability to negotiate."
He is yet to have discussions with either Labour or National about possible Epsom-style arrangements.
"It's an independent party - that's the point and it has to be. It's very important to me that that's what it is. So really, the point is that people have a party they can vote for that can always be in Government."
To get into Parliament, the Sustainable NZ Party would have to either get 5 percent of the vote or win an electorate seat. History is against Mr Tava - neither have been achieved by a party that wasn't set up by a former MP since the first MMP election in 1996.
The Conservative Party came closest, getting 4 percent of the vote in 2014.
Mr Tava currently serves on the Waitematā Local Board.