Bay of Plenty MP Todd Muller has released a statement on Friday morning saying he will not be contesting the next General Election in October.

"When I entered parliament in 2014, I was determined to bring the best of myself to this special place. In the subsequent nine years I have tried to give my absolute all for my community and my country," says Muller.

"In all jobs there comes a time when, if you are honest, you start lacking the enthusiasm and energy you once had.

"After much reflection and discussion with those close to me and who know me best I have realised I have reached that point. I will not contest the next election. I cannot recommit to giving the National Party nor my BOP community another full three-year term."

Todd Muller's full statement acknowledges the support of his family and electorate, and the journey he has been on since entering politics.

"I can't deny this is a hard decision. Christopher Luxon and Nicola Willis have completely reset the caucus and I firmly believe they will provide tremendous leadership at a time of great challenges for our country come October. Their support for me personally and professionally has been unequivocal and I wish to thank them for their genuine values-based leadership," says Muller.

National's Leader Christopher Luxon has issued a statement thanking Muller for his service.

"Todd Muller has been a deep-thinking and hard-working member of National's team in Parliament and I thank him for his service to the party, the public and the people of the Bay of Plenty," says Luxon.

'Politics requires an enormous commitment to do the job well and I respect Todd's decision to call time and retire from Parliament at the upcoming election.

'Every politician needs a team behind them and I thank Todd's family, current and former staff, and party members in his electorate for their support of him," says Luxon.

Luxon says Muller gives 110 per cent of himself to whatever he does.

"I wish him and his family all the very best for the future."

The National Party leader has announced that Todd McClay will become National's Agriculture spokesperson, bringing together the Agriculture and Trade portfolios under one spokesperson.

"Todd will lead National's strong agriculture team of MPs and candidates, including Nicola Grigg, Joseph Mooney, Suze Redmayne, and Miles Anderson," says Luxon.

'Agriculture does much of the heavy lifting in our economy – creating jobs, lifting incomes and feeding people all over the world. National will campaign up and down the country to stop Labour's war on farmers.

'Simon Watts will take on the Climate Change portfolio in addition to his current responsibilities of Local Government and Regional Development. National is deeply committed to New Zealand reaching the greenhouse gas emissions reduction targets that it signed up to in the Paris Accords and achieving net-zero by 2050."

Luxon says Joseph Mooney will take on the Tourism portfolio which is currently held by Todd McClay and Chris Penk will become National's Cyclone Recovery spokesperson.

Full statement from Todd Muller:

Since I was a young boy I wished to be an MP. When I entered parliament in 2014, I was determined to bring the best of myself to this special place. In the subsequent nine years I have tried to give my absolute all for my community and my country.

In all jobs there comes a time when, if you are honest, you start lacking the enthusiasm and energy you once had.

After much reflection and discussion with those close to me and who know me best I have realised I have reached that point. I will not contest the next election. I cannot recommit to giving the National Party nor my BOP community another full three-year term.

The upcoming election is the right time for me to step down, to pursue new challenges and allow a new National candidate with fire in their belly to take on the role of MP for the Bay of Plenty seat.

I can't deny this is a hard decision. Christopher Luxon and Nicola Willis have completely reset the caucus and I firmly believe they will provide tremendous leadership at a time of great challenges for our country come October. Their support for me personally and professionally has been unequivocal and I wish to thank them for their genuine values-based leadership.

My journey in politics has been a stimulating, challenging and at times difficult ride. However, I am thankful for it all. I am a changed person through my parliamentary experience, and I hope adversity has broadened my understanding and care for the many forms of exasperation and inspiration that exist in our community.

The times of most satisfaction were the quiet words to help locals navigate the often bewildering public service, successfully advocating for greater infrastructure and services for Tauranga and the Agriculture and Climate Change portfolios - the two underpinning pillars of our current and future society.

I love my community and I love this country. It has been an absolute privilege to have been elected three times by the people of the Bay of Plenty electorate to serve them.

I want to express my deep gratitude to my incredibly loyal party members in the Bay of Plenty electorate. Your support and care for me and my family has been incredible. What a ride we have been on with you all. To my staff (present and past) in Wellington and Papamoa, thank you for all your hard work and care for our constituents. I couldn't have done it without you.

Finally, to my family, thank you for your patience and support as I've served our community, often at the expense of time with you. You are my rocks and I love you very much.