Director-General of Health Ashley Bloomfield is stepping down from his role at the end of July.
Public Service Commissioner Peter Hughes revealed Dr Bloomfield's decision in a statement this morning.
Bloomfield had signalled to the commissioner late last year he intended to step down before his term officially ended on 11 June 2023, Hughes said.
He said Bloomfield had done an outstanding job leading the government's health response to Covid-19 and the vaccination rollout.
"Dr Bloomfield has worked tirelessly for more than two years to keep New Zealanders safe from coronavirus," Hughes said.
"Dr Bloomfield has demonstrated remarkable resilience and courage in leading the health system's overall response to Covid-19. That response has saved lives.
"I thank Dr Bloomfield for his commitment to public service, his spirit of service to the community and his exceptional contribution to New Zealand's Covid-19 response. I know many New Zealanders will also be thankful for the job he has done."
Hughes said Bloomfield wanted to stay on until the country had a good hold on the virus, and that time was now.
In a post on Facebook, Prime Minister Jacinda Ardern said Bloomfield had been a true public servant in every sense, through his dedication, drive and calmness.
"He has been central to our COVID success as a nation, and he's done it with humour and grace (I'll keep the details of his sporadic mockery of me to myself!)
"When we spoke about his decision to move on, he mentioned that he wanted to spend time with his family, and that's the least we owe him. So kia ora from across the Motu, Dr Bloomfield. We thank you."
She told reporters this afternoon she could not imagine a better example of a true public servant.
"He has been tireless, he has been dedicated, he has taken an enormous load and he has contributed to the success that New Zelaand has had in keeping peopel safe through this pandemic.
"There's also been the odd light moment. You'll have seen glimpses of Dr Ashley Bloomfield's sense of humour, I was privy to that on occasion and I was the butt of it on occasion, but it's been a privilege."
She said he had told her he wanted to spent more time with family and "after what he's helped lead New Zealand through over these past few years I think he's really entitled to that."
Covid-19 Response Minister Chris Hipkins also posted on Facebook after the news was released, acknowledging Bloomfield for being a "reassuring figure" through the pandemic response.
"The amount of pressure he's absorbed, and the level of commitment he's shown over the past two years make that an easy decision to understand.
"We thank you Ashley for all you've done to keep us all safe. Give the man a beer, he's truly earned it!"
National's leader Christopher Luxon was similarly full of praise and he wanted "to just say he's worked incredibly hard, to thank him for his service and I hope he gets a well deserved break and to wish him well for his future.
"We of course have had issues at different times with the health response, vaccination rollout, rapid antigen tests, but those issues sit with the prime minister and the minister for covid response, not with a public servant."
The party's Covid-19 Response Spokesperson Chris Bishop also thanked Bloomfield for his "years of service to New Zealand at a very very difficult time for New Zealand, a very very challenging role".
"When you think back on it, senior public servants don't typically end up with such a public profile and t-shirts and cups and mugs being made about them, and that's appropriate because public servants are typically out of the limelight.
"I think it's been a weird time - all sorts of weird things have happened, ministers have said strange things about spreading legs and all sorts of things ... I just hope that we get to 2030 and we don't have any more Covid.
National Party health spokesperson Shane Reti told Midday Report he was thankful to Bloomfield for his service in this role and previous senior leadership roles in DHBs.
He said he wished him well for his next endeavour.
ACT leader David Seymour bucked the trend, describing the execution of the response
"I'm sad to see anyone who's worked hard to serve the New Zealand public move on but I think we've got to be honest, he's not Saint Ashley if you consider the failings of the department he was responsible for - which are considerable.
"He'll be remembered as a charming guy but the basic operational execution of our covid response has been disastrous. PPE wasn't there, testing - disaster - contact tracing never reached the gold standard, vaccine rollout didn't involve GPs and was well behind time especially for minorities.
"When you sum all that up we're just damn lucky that we're an island that had MIQ."
He said the country's low death rates were because New Zealand is an isolated nation that had a very strong border, and the ministry could not be credited for that.
Green Party co-leader Marama Davidson had the opposite reaction.
"Being one of the coolest Director-Generals to have to be in front of us every day almost for the past two years, I think it's clear that everyone realised that he genuinely cared, I think people could see that, could sense that when he was in front of us all - day after day - that he genuinely cared about this work and was giving his all."
She said she hoped whoever took over the role would continue to listen to Māori experts and health providers.
An acting director-general will be appointed before Bloomfield finishes on 29 July, 2022.
Bloomfield's previous comments on work
At a conference for GPs last year in August, Bloomfield said his role was full on even without a pandemic.
"Nothing can really prepare you for this. I have to say for the first three weeks, some of you may have heard me say this before, I would wake up about three in the morning, every night, with a cold sweat.
"It was just moving so rapidly and there was so much at stake with the advice we were giving and the decisions that had to be made that I would wake up at three in the morning, and I know I wasn't the only one, thinking 'oh my goodness, where is this going, I'm going to give the wrong advice, and something is going to go terribly wrong'.
"I have to say the 1 O'clock stand-ups came to feel like sort of performance review on live television every day."
He said he was grateful for being blessed with good health, physically and mentally.
"I've been in a chief executive role for quite a while, I've been in senior leadership roles, but I had a couple of moments last year where I thought, 'holy heck, I'm really butting up against the edge of my resilience here'.
"It came home to me one day when I didn't have a media stand-up and I realised about 10 O'clock my cortisol had gone through the roof, I was sweating, my hear rate was up, I was really quite anxious.
"Normally, I would be able to focus all that on preparing mentally and of course doing the work ahead of the stand-up ... and because I didn't have that, my body was still going into overdrive and had nothing and so I thought 'okay, time to take a holiday'. So I did, and that made national news I think.
"But the key point here is it was a reminder to me that resilient people are not people who just keep going through thick and thin, resilient people are the one who know their limits, they know what those boundaries are."