Labour MP Kiritapu Allan has revealed she has been diagnosed with stage three cervical cancer.
Prime Minister Jacinda Ardern said she was gutted by the news after Allan's public announcement sparked an outpouring of support from her party colleagues.
Her comments were echoed by National Party leader Judith Collins, who said Allan's public declaration was very brave and would inspire others.
"The fact that she had to deal with the Civil Defence issues, while she knew this was all happening really does speak volumes about her dedication and courage."
In a Facebook post this morning, the emergency management and conservation minister said she was diagnosed last week, and the fight of her life has now begun.
The East Coast Labour MP said: "Last year, during the campaign I noticed I was getting a lot of pain in my back, stomach and legs. I put it down to lots of driving, working long hours and the general stress of campaigns.
"Earlier this year, I realised I was finding it hard to sit for a lengthy period of time. Always in a bit of pain. I started running to try and move the lower back area a little bit. Nothing seemed to take the pain away."
Allan said in late January in the car, she began menstruating and it didn't stop.
"At about 6 weeks of menstruating with no change since the GP visit, I raised it with my colleague and friend, Ayesha Verrall who is a doctor, asking if the bleeding was a little odd. She asked a few more questions and I told her about the pain. She urged me, pleaded with me, "Kiri, please, please, please prioritise this and go to the doctor tomorrow." She made some recommendations and the next day I found myself having an ultra sound," she said.
Allan said the ultrasound found a three centimetre growth and her doctor made arrangements to go to hospital the next day for a follow up.
That day happened to be when three large earthquakes struck off the coast of New Zealand.
"I found myself managing the earthquakes early morning, then headed the hospital for another ultra sound at about 8am (just before the large evacuation notice - poor timing!)," she said.
"They found the growth was approx. 6cm but likely benign. We had a chat about options for removal. By and large, things seemed ok and I could get back to work that day. So I arrived back just in time for the 11.30am stand up at the beehive."
Allan said she then had to undergo a colposcopy.
"A handful of days later, I was jumping off a flight from Christchurch where I had been doing an RMA meeting and launching a community waterways partnership project, into Auckland where I was off to launch a Kiwis for Kiwi project with Sir John Key and Helen Clark the co-ambassadors for the project.
Kiri Allan has revealed she has been diagnosed with stage three cervical cancer. Photo: Facebook/Kiri Allan
"I saw I had a missed call from the doctor with a text follow up to give her a call. I called back, going down the escalator stairs and the sound was rubbish. I skirted off to a corner to take the call properly, expecting good news.
"However, my kind doctor, who had been so incredible and taken calls from my family in the evenings, called to say the colposcopy had revealed I had cervical cancer."
Prime Minister Jacinda Ardern said: "As a friend and a colleague I've been gutted by the news, her whole team is.
But we are also so heartened by the character, the person that Kiri is. Right from the outset she has shown a level of determination to focus on her health and wellbeing, but to ultimately come back and be a part of the team. "
Ardern said their focus was to make sure Allan was prioritising herself.
Ardern said Allan fronting the public through a Civil Defence emergency while in the middle of her diagnosis had been exceptional.
"As I saw the praise for her management of that, I thought if only people knew what else she was dealing with - it was remarkable, but she is remarkable."
Doctor and Minister for Food Safety Ayesha Verrall - who Allan had consulted about her symptoms - was visibly upset as she spoke about the confirmed diagnosis.
"I'm really, really sad for my friend," she said.
"Kiri told me about she was feeling unwell and I encouraged her to get her symptoms checked.
"Cervical cancer is a really nasty disease, and it strikes women right in the middle of their lives when they have so much to give to their communities and their families."
Verrall encouraged women to take two vital steps - get the vaccination and ensure their smear tests were up to date.
Māori Development Minister Willie Jackson said he was shocked and saddened to hear the news.
"She's a wonderful performer and we're very proud of her in terms of her contribution for our people," he said.
"We are sort of having a karakia for her at the moment, but she's strong and we've got a lot of hopes for her."
Minister of Internal Affairs Jan Tinetti, who had her own battle with breast cancer, said she was devastated.
Her advice to Allen was to forget about Parliament and put herself and her whānau first.
"She's got every bit of my support that I possibly can give."
Reflecting on her own diagnosis, she said "It's a really terrible time".
"Just that sense of unbelief... I know exactly how she's feeling at this time."
Allan said she was taking medical leave to focus on "the fight I have ahead of me".
She said Ardern will be appointing acting ministers to her portfolios.
Allan said her and her whānau are requesting privacy while they come to terms with the challenge ahead.