Prime Minister John Key will go down as one of New Zealand's greatest Prime Ministers, according to Bay of Plenty MP Todd Muller.

He says he was gobsmacked when he learned this afternoon that John would step down from office next Monday, citing family reasons. John wants to spend more time with them.

'I was not expecting that news at all.

'But the more I reflect on his decision and comments, the more respect I have. It would be a very difficult thing stepping away from power after leading National to three successive election victories, each time with a larger margin.”

Todd says the Prime Minister decided he couldn't see this thing through for a full fourth term.

'So opposed to standing and knowing he wasn't going to do it for a full term, that doesn't have integrity, he stepped down and will leave on top.”

Todd says the timing is right – it gives the party time to find a new leader and deputy leader and have them embedded in time to fight an election next year.

And he doesn't think Labour should see this as any sort of shift of fortunes.

'The ability to win an election comes down to your ability to sell a vision for a country. And in my opinion Labour is devoid of leadership and vision. The Prime Minister stepping aside does not fix their problems.”

Todd says National has a very strong record of performance and constantly striving to do better for the country in a highly unstable time globally.

"We will take that plan to the country next year."

But he won't speculate on leadership. But he agrees the choices are critical.

'You saw that with Key and Bill English. The strength was in the power on the two of them so we need to reflectively carefully and fully.”

The MP doesn't have leadership aspirations, not yet. 'But how kind of you to ask.”

The MP's office hadn't heard a whisper until a woman rang and told them 'the evil man was gone”.

Mayor Greg Brownless was told of the resignation at the start of a meeting discussing civil defence issues.

'I was surprised, never saw that coming at all,” he says speaking to SunLive after the meeting.

'I think whilst it always looks good from the outside, having a positon such as that, the endless travel, the endless pressures on family life, and the endless criticism and blame no matter what you do, must eventually wear you down.

'From what I've seen that's what it was. Didn't he says he has run out of battery or something?

'And I could see how that could happen after being in that sort of job for a long time. As a Prime Minister, or indeed a mayor, everything falls onto you. I guess after a while you begin to think other things take a priority in your life.

'Good on him for seeing that.”

Like Pope Benedict, who in 2013 became the first pope to retire since the 15^th century, Greg says there are not too many people who can actually resign from those type of positions. Most wait until they don't get appointed any more.

'Making a decision like that regardless of what side of the political spectrum, you say well, hey you have made that decision and best wishes.”

Tauranga Chamber of Commerce CEO Stan Gregic says he doesn't see anything too significant in the announcement.

'I see the dollar has dipped a little bit. I imagine that is going to stabilise once the successor has been confirmed.

'Whether that's Bill English of Steven Joyce, there's probably not much in it to be honest.

'I just see it as business as usual. Having someone new and fresh there, though neither of those two are new and fresh - at least it gives the government a chance to kind of re-positon itself and go back on the initiative on some fronts.”

Priority One CEO Nigel Tutt says the announced resignation seems to be a very controlled process, one that would provide stability.

'And that's important for our region.

'He appears to be doing it with the best interests of the stability of the country at heart and that's got to be applauded, good for businesses and the community as well.”