Speaker of the House Trevor Mallard will formally resign from the role at 1.45pm on Wednesday 24 August.
Speaker Trevor Mallard in the House Photo: ©VNP / Phil Smith
The long-anticipated resignation has been accepted by the governor-general.
Current Deputy Speaker Adrian Rurawhe will most likely replace Mallard.
Labour has made it clear Rurawhe was being prepared for the role for some months.
Mallard's resignation came as Minister of Foreign Affairs Nanaia Mahuta formally announced his diplomatic posting as the next ambassador to Ireland.
"As New Zealand's second resident Ambassador to Ireland since the opening of our Embassy in Dublin in 2018, I am delighted that the strong relationship between our countries will continue to be in excellent hands with the appointment of Mr Mallard," she said.
Mallard has been Speaker of the New Zealand House of Representatives since 2017 and a Member of Parliament for 35 years.
Over that time he has held 13 ministerial portfolios, including education, labour, state services and the Rugby World Cup.
He announced his resignation from Parliament in June and will be the third of the five most recent speakers to represent New Zealand overseas in a diplomatic posting.
"Our countries share a great deal in common as principled, independently-minded and outward looking nations. We co-operate on issues such as climate change, disarmament, and peace & security issues," Mahuta said.
"We also look forward to our strong agricultural, trade and economic links deepening further in the coming years, including in light of the recent conclusion of the New Zealand - European Union Free Trade Agreement negotiations. Ireland's continuing support for the FTA has been appreciated," Nanaia Mahuta said.
Mallard is expected to take up his role in January 2023.