A strong government performance this year is likely to win over swinging voters, PM believes.

The Prime Minister is launching into 2016 with plans to stand for an historic fourth term.

In a wide-ranging interview with the Weekend Herald about the year ahead, John Key confirmed his intention to fight another election and remain in office. "My stock standard position has been that I intend to stay for as long as I think I can add value and the party wants me," he said.

"That's my position. It's not something where I've gone away and actively considered but that is my position at the moment."

He is back at work after spending Christmas with family in his holiday home on Maui, Hawaii, followed by a road-trip with his wife, Bronagh, from Los Angeles to San Francisco.


Tomorrow afternoon he will be welcomed on to the marae at Ratana with other politicians.

And on Tuesday, after Wellington Anniversary Day on Monday, he will chair the first Cabinet of the year - although it will be without Finance Minister Bill English and Transport Minister Simon Bridges who will be visiting the Antarctic.

Mr Key said this year would be an important one for the Government because in reality, it was a lot harder to get things done next year.

He believed people cemented their voting intentions a lot earlier than many commentators thought.

"I'm not saying campaigns don't matter at the margins - they certainly can and do change voting patterns within the margins and within different blocs. But if swinging voters see a strong performance this year, they are much more likely to vote for us next year."

He said he wanted this year to be similar to other years in which he tried to deliver results "to keep earning the right to be there".

He implied there was disconnection between National's high poll rating (51.3 per cent in the December DigiPoll survey) and what he called "the noise" in the media about the Government's performance.

"The things that people really look to the Government for, economic performance, health, education, law and order, the Government has been delivering improving results to people."

I intend to stay for as long as I think I can add value and the party wants me.

Asked how he was going to lift living standards for New Zealanders he said: "In the same way we have in the past. In the main areas that count for people: interest rates, inflation, and real growth, you've got to have them occurring in a positive way."

Auckland was a market dominated by people with larger mortgages because of high house prices.

"For those people and for that group of voters, the two things that are really critical are interest rates staying low and the job market staying strong. So if they lose their job there is opportunity and that their mortgages don't climb despite the nominal size of their mortgage."

Auckland housing would continue to be a big focus of attention this year to avoid a housing bubble and to help first-home buyers get on to the ladder.

"But I don't think there is ever going to be one single thing you can do."

Everything the Government had done had generally been working.

"I suspect you'll see increases in house prices this year but at a much lower rate than we saw in 2015."

Radio spots a slippery job

John Key says he won't change his approach to commercial radio despite being lured into a cage in a studio where he became part of a "gag" about male rape in prisons.

He left for a Christmas holiday in Hawaii and California without commenting on publicity around the antics but, in his first interview of the new year, he told the Weekend Herald there were always risks with commercial radio.

"If I really want to eliminate all those risks, I'd have to stop going on them," he said. "I'm not going to stop going on commercial radio stations because, in the end, that has been an important way for me to communicate with a broad audience, some of whom are only very tangentially interested in politics."

He said he had had no idea what The Rock had in store for him when he was asked to join Tom Furniss in a cage in the studio, other than the host was going to get "100 likes" on Facebook if he joined him.

Once he was inside, Furniss asked him to pick up a bar of soap, which he did, not knowing it was a reference to prison rape.

He said he had not known what the context was around the reference. And in fact when the host dropped the soap, he had said it had been in the toilet.

"That's what I thought the joke was. I can't stop these guys from doing some slightly crazy stuff.

"All I could do is not go on any of those shows but there are an awful lot of commercial radio stations and I'm on a hell of a lot of them during the course of the year."