Former National leader Todd Muller has decided to step down at the next election to prioritise his health and family.
Muller said in a statement on Wednesday it was a "difficult" decision to make, because being MP for Bay of Plenty is a "huge privilege", but the former party leader said being a politician "does come with a cost".
"In announcing today, I hope to give the National Party and my local branches ample time to find their next candidate. The National Party needs to take the opportunity this term, to renew and refresh, with strong new candidates lining up for the next election.
"I look forward to working out my term with the National team. In the meantime, I am on pre-approved leave for the next five weeks, to care for my wife who is undergoing a significant medical procedure. I will return to Parliament after the winter recess.
"I have decided that I need to prioritise my health and family and move onto the next chapter of my life."
Muller resigned as National leader in July last year after less than 60 days in the role. He became leader after rolling Simon Bridges. Muller's deputy was former Auckland Central MP Nikki Kaye.
The day Muller stepped down, Judith Collins was elected by the party as leader, with Gerry Brownlee as her deputy. Brownlee has since stepped down from the deputy role, which was filled by incumbent Dr Shane Reti.
Muller has talked about how becoming leader led to anxiety panic attacks, which ultimately led him to step down after a short time in the role.
Muller said he was "very proud" of the work he did with Climate Change Minister James Shaw in creating "bi-partisan support for climate action" and "achieving cross party support" for the Zero Carbon Act.
Muller's support for climate action and endorsement of the School Strike 4 Climate earlier this year appeared to be in contrast to current leader Collins, who says kids will grow out of climate activism.
He says serving his community has also been a highlight of being an MP.
"I particularly enjoy working with my various local communities from Papamoa to Omokoroa pushing hard for the amenities and infrastructure that our growing region deserves.
"I can assure them all I won't stop advocating for mental health facilities, after hours A&E and roads for my remaining time as their MP."