Former Porirua Mayor Nick Leggett says he has dropped plans to seek the National Party nomination in Mana.

Leggett said he no longer wanted to run for Parliament, but would help National with its election campaign this year.

"I've thought about it and I'm going to sit this one and focus on getting some non-political experience," he said.

"I'm pretty keen to separate me joining the National Party from me wanting to be an MP.

"The important part of my decision was saying that for moderate people like myself I see the future as being with the party who's open to trade and playing our part as an international citizen, and that's the National Party."

Leggett said he wanted to "earn his political stripes" with National before deciding whether to run as a candidate in future.

He was an admirer of former Prime Minister John Key, but said Key's resignation did not influence his decision not to run for Parliament.

Leggett was Porirua Mayor from 2010 to 2016 and a long-standing Labour Party member until he contested the Wellington mayoralty last year, which pitched him against Labour's candidate Justin Lester.

Once described by Labour leader Andrew Little as "too right-wing", Leggett became disillusioned with Labour because of its opposition to the Trans Pacific Partnership, immigration, and the Iraq deployment.

Labour's formal alliance with the Greens for the 2017 election campaign also influenced his decision to quit the party.

Leggett joined National in November and said he planned to seek the nomination for Mana, where he was well known from his time as mayor.

The Mana seat is held by Labour's Kris Faafoi, who won with a 7953-vote majority in 2014.

National's current Mana candidate, Hekia Parata, is quitting Parliament at the election.