LIVE: The contest to replace John Key is under way with candidates for PM declaring their hands.
Follow live updates and reaction here.
At a glance
- Deputy Prime Minister Bill English, Health Minister Jonathan Coleman and Police Minister Judith Collins have all confirmed they'll run for the top job
- Several ministers have already declared support for Mr English: Michael Woodhouse, Nathan Guy, Nikki Kaye, Anne Tolley and Hekia Parata - as well as John Key
- Senior ministers Simon Bridges, Gerry Brownlee, Paula Bennett and Amy Adams have so far refused to say whether they will support Bill English if he runs, or if they plan to contest the leadership themselves
Barring a late announcement, we're wrapping up this blog for the day - as things stand we have three contenders for the next Prime Minister: Coleman, Collins, and English. Will Bennett, Bridges and Brownlee throw themselves into the melee?
More from Judith Collins' brief stand-up earlier this afternoon.
Ms Collins was asked if it was important to have a woman in the race, with "two white men" the other contenders.
"Well it's been like that for quite some time", she said.
"I think it's actually really important that the best people for the jobs get them and I happen to think I am in fact, one of those people."
Can she work with Winston Peters?
"I can work with anyone."
Leadership contender Jonathan Coleman says it's "great" Ms Collins has joined the race and he's not worried about possible divisions within the party now that there are three options.
"Once we've made this decision we've all got to get behind the winner."
He hopes to be that winner - "obviously".
Has Collins got the numbers? "This is something we will find out [next] Monday."
Judith Collins is thronged by reporters as she announces her run for the leadership just before Question Time.
Judith Collins is in, she has just confirmed.
Judith Collins might be keeping mum on the leadership contest, but Lord Ashcroft (better known for chipping in the odd philanthropic million here and there) reckons she's a contender.
@JudithCollinsMP go on....— Lord Ashcroft (@LordAshcroft) December 5, 2016
Nikki Kaye is standing ... for Auckland Central. The sitting MP used her brief return to Parliament to announce that she plans to defend the seat in next year's general election.
Judith Collins still won't rule herself in or out. "I'm still taking some soundings and if I do I'll make an announcement in the very near future."
He says he could work with Winston Peters - "I've got the experience of four coalition governments".
Bill English says he's "older and wiser" since he last led National in 2002, when it posted its worst-ever election result.
Other MPs are emerging from caucus. Among them is Auckland Central MP Nikki Kaye, who has returned to Parliament briefly while undergoing treatment for breast cancer.
She, along with John Key, Michael Woodhouse, Nathan Guy, Anne Tolley and Hekia Parata will back Mr English.
Bill English says he hasn't made any decision about who might be his deputy if he wins, or if he'll run on a ticket.
He says he's been "intimately involved" in the policies of the John Key-led government and can see "fantastic opportunities" to spread the benefits of economic growth to all New Zealanders, "and getting stuck into some of our most intractable social problems".
Bill English officially throws his hat in the ring.
Gerry Brownlee has wandered past as reporters wait for Mr English. He's still refusing to say who he'll back.
Bill English has emerged but is making media head down the corridor to the black and white tiles near the debating chamber before he'll answer questions.
Coleman will run for leader.
Jonathan Coleman is addressing media outside the caucus room.
Nick Smith has briefly emerged from caucus, without saying anything to waiting reporters.
RNZ deputy political editor Chris Bramwell is keeping a close eye on caucus comings and goings
Bridges and Williamson leave the caucus room in a hurry— Chris Bramwell (@ChrisBramwell) December 5, 2016
Amy Adams, along with Cabinet colleague Simon Bridges, has joined the list of those refusing to say whether they'll run for either leader or deputy.
Here's Amy Adams - who has been tipped as a possible deputy - talking to reporters prior to caucus.
As the National caucus meeting rolls on, John Key has excused himself from the room so that MPs can discuss the procedure to select a new leader.
Economic commentator Rod Oram says the government under John Key hasn't delivered on the main things it pinned its economic performance on.
"We were going to have massive uptake of exploration in oil and gas ... That hasn't happened.
"We were also going to get a doubling of exports ... No way are we going to achieve that."
Mr Oram says he finds it "kind of interesting" that Mr Key is leaving office with so much political capital unspent.
Here's Bill English on his way into caucus earlier this morning.
And his senior colleague Steven Joyce, who was the next most popular alternative leader behind Mr English in a UMR survey conducted - rather presciently - in September and October.
Senior minister Jonathan Coleman says he is considering a tilt at the leadership.
He told reporters on his way into caucus that he had been "taking some soundings, not doing numbers, but seeing what the appetite of the caucus for a contest is".
Matthew Hooton "I think what he believes in is stability and I think Helen Clark also believed in that."
His original assessment was that Working For Families was 'communism by stealth'.
"The fact that he's claiming both of those, retaining and improving Working For Families and increasing benefits as part of his legacy is an odd thing to claim," says Stephen Mills.
Stephen Mills tells Kathryn Ryan John Key was a "trader"
"I think his legacy as a prime minister is very mixed and I certainly don't think he used his political capital at all."
MPs are now in caucus to discuss how the contest will be handled.
Mr Key says there's an opportunity for leaders, apart from Bill English to emerge.
Mr Key denies that he shied away from making tough decisions during his tenure which could have affected his popularity.
John Key says his hard stance on NOT raising the age of superannuation was NOT a mistake.
John Key believes his government has done some things to address housing affordability.
John Key tells Kathryn Ryan he hadn't been feeling under anymore pressure in the job than previously.
Stephen Mills says it may well be that Bill English does succeed but there will almost certainly be a contest and people like Jonathan Coleman and Amy Adams might see themselves as change agents.
UMR Research's executive director Stephen Mills says there's a rising understanding that a "Key government without John Key will not be successful. So the new prime minister needs to do something new."
Kathryn Ryan from Nine to Noon speaks to political commentators Matthew Hooton and Stephen Mills.
Potential leadership contender Judith Collins arrives at Parliament saying nothing about whether or not she'll stand.
Media across the Tasman continue to digest the news ...
Two National Party ministers Nathan Guy and Michael Woodhouse have expressed their support for Bill English as they arrive for caucus.
Backbenchers Mark Mitchell, Alfred Ngaro and David Bennett are NOT commenting on who they'll support until they know who the contenders are.
John Key regrets that wee vote on the flag.
Peter Goodfellow says he spoke to Bill English yesterday, the only MP he's spoken to since the announcement.
National Party president Peter Goodfellow - "if there's more than one who wants to be the leader, then there should be a contest for that."
John Johansson says there is significant down-side risk for National and the 26 years Bill English has served in office accentuates longevity rather than freshness.
Senior lecturer in Comparative Politics at Victoria University John Johansson says John Key's resignation could potentially be an unravelling for National.
Based on that survey - Stephen Mills - "You can certainly conclude at that stage there was no natural successor to John Key."
UMR Research recently carried out an online survey, if John Key was to go, who would people want as leader?
21 percent - Bill English
16 percent - Stephen Joyce
11 percent - Paula Bennett
6 percent - Judith Collins
45 percent - unsure
David Farrar says Labour has an opportunity to become more relevant but on the positive side for National, they can be seen as more of a fresh first term party with a new leader.
David Farrar "you'd have to think Bill English is the favourite to win."
Executive director of UMR Research Stephen Mills and National Party pollster David Farrar are on the show.
Mr Brash says Bill English has grown a lot and commands the respect of the business community as a very steady pair of hands.
Mr Brash would like to see Judith Collins succeed Mr Key and says the party has a number of people who could be good leaders.
Don Brash says Mr Key has not dealt well with crunchy issues of narrowing the wage gap with Australia, superannuation and housing.
Don Brash is another former leader who resigned and was replaced by John Key and he's critical of Mr Key's performance as prime minister.
"There's no one better giving an after-dinner speech than John Key... but has he tackled the big issues facing New Zealand, unfortunately not."
"Just as John has broken the rules historically around clichés and presumptions as to how politics and politicians will act I think we're seeing the continued evolution, and it's much better for us, we're defining our own future."
Dame Jenny says there's huge talent in the National Party.
Dame Jenny Shipley: "This rather sort of plain, nerdy, but highly successful person wanted to transfer his skills."
"He was very clear he wanted to come in, he wanted to make a difference, and he said he wanted to be prime minister."
Former Prime Minister Dame Jenny Shipley helped recruit John Key as an MP back in 2001. She says she saw a passion in him for wanting to move ahead.
Former National party leader Don Brash:
"He's jovial, he's friendly, he's cordial ... he's very much seen as one of us and in that sense he's done a good job. But has he tackled the big issues facing New Zealand? Unfortunately not."
More from Don Brash coming up on the programme.
Why John Key, Resigning As Prime Minister Of New Zealand, Is Like Hugh Grant https://t.co/AjqrE9IKuD— Newsdesk Film (@NewsdeskFILM) December 5, 2016
Former Prime Minister Jenny Shipley coming up on Morning Report.
Marama Fox says she looks foward to Bill English coming in, thinks he's the logical choice for PM.
Maori Party co-leader Marama Fox rejects Hone Harawira's assertion that the party rode on the coattails of John Key.
Mr Little says John Key is a formidable presence and says while the landscape has changed the fight to win next year's election is the same.
Andrew Little says the Mt Roskill by-election result was a slam-dunk against National.
Labour leader Andrew Little says John Key was losing his lustre.
I guess John Key won't be going back to Waitangi after all...that'll send the marae committee into a spin - we *just* sent the invite! pic.twitter.com/7qktg08yRY— Maiki Sherman (@MaikiSherman) December 5, 2016
Mr Harawira says naked greed has been the hallmark of Mr Key's tenure and Māori have suffered massive loss during that time.
Mana leader Hone Harawira says John Key has been a great leader for the rich.
Winston Peters says he predicted yesterday's announcements.
Winston Peters says resignation wasn't a surprise to the New Zealand First Party.
John Key says Judith Collins "could" have what it takes to be leader.
John Key on Bill English "I genuinely believe in the guy."
Mr Key's biggest regret - "at a somewhat superficial level not getting the flag through, although I accepts it's not the most important issue."
John Key thinks economic leadership will be his legacy and steering the country through difficult times, including the Christchurch earthquake.
John Key thinks it's the dream of any politician to end at the top of their game.
Political editor Jane Patterson says Bill English is the front-runner for the leadership at the moment. She says he was looking very happy and pretty relaxed when he spoke to reporters yesterday. She says Mr English will want to be sure he has enough support before deciding to put his name forward.
Political editor Jane Patterson believes contenders could be waiting for Bill English to make first move.
Gerry Brownlee not prepared to make any declaration either way on his intentions.
Mr Brownlee doesn't think a contest for the leadership will hurt the National Party.
Describes the party as quite different to the one in the 90s.
Leader of the House, National MP Gerry Brownlee says they have got a calm caucus.
Former National party leader Don Brash says John Key has enjoyed being Prime Minister and ego-boosting meetings with world leaders but he has been guilty of tinkering rather than making major changes.
He says Mr Key has not dealt well with crunchy issues of narrowing the wage gap with Australia, superannuation and housing.
Mr Brash gave him a five out of 10 for his time as Prime Minister, saying he had not done anything that Helen Clark would not have done.
The Council of Trade Unions says John Key's legacy is one of people working longer hours for little reward.
CTU secretary, Sam Huggard says workers have not enjoyed their fair share of the expanding economic pie under the leadership of departing Prime Minister, John Key.
He says the government's labour laws have strengthened the hand of employers.
United Future leader Peter Dunne says Bill English is a logical choice, has the country's confidence.
Good morning, the National Party caucus is meeting this morning to discuss the process for selecting their new leader and deputy leaders.
We will bring you all the news and reaction on day two, starting with Morning Report.