National list MP Chris Auchinvole has confirmed he is one of a number of National MPs planning to step down at next year's general election.
Internal Affairs Minister Chris Tremain said on Monday he would not contest the Napier seat he has held for almost a decade.
Prime Minister John Key indicated he anticipated "one or two" more would follow suit, but declined to say who.
Auchinvole said yesterday he intended to resign. "One could say leaning towards retirement. You never have enough, but I am 68 now, I'd be 70 shortly after the next election. It is my intention to retire from party politics."
He said he had a "number of really good opportunities in the commercial world" to pursue.
The Scottish-born MP entered Parliament, as a list MP, in 2005 "along with half the caucus".
In 2008 he won the West Coast-Tasman seat from Labour MP Damien O'Connor, who regained it in 2011.
Other MPs expected to stand aside are Invercargill MP Eric Roy and Hunua MP Paul Hutchison, who are both 65.
Hutchison would not say if he was planning to stand again. Those planning to resign "will reveal their names when the time is appropriate", he said.
He was first elected to Port Waikato in 1999, succeeding former National minister of finance Bill Birch. The electorate is now known as Hunua and is a safe National seat.
Invercargill is known for being a bellwether electorate.
Roy, who is also the deputy Speaker, has served 17 years in Parliament.
He is currently in the US and did not return calls.
Kaikoura MP Colin King is understood to be facing a battle for selection in his electorate from local winery boss Stuart Smith. He was first elected in 2005.
The 63-year-old King said yesterday that he intended to seek nomination.
"I am not doing a Chris Tremain . . . I'm pretty confident I will get the nomination if I go for it."
Tremain said he was stepping down to spend more time with his family.
- Fairfax Media
Should Murray McCully stand down over the diplomat sex allegations case?Related story: McCully should stand down - Greens