The current co-leader, James Shaw, stands down from the position next month. Marama Davidson is the other co-leader.
Alex Foulkes, 48, said he was standing to ensure there was a lively debate about the future of the Green Party and Aotearoa.
On Saturday evening, a Green Party spokesperson confirmed to RNZ that Foulkes had announced his intention to run, but he was yet to submit his nomination.
Foulkes said the time was right for the Greens to displace Labour as the main left-of-centre party and become the party of the working class.
Born in Edinburgh, Foulkes emigrated from the United Kingdom to New Zealand in 2002 and has worked on several conservation projects around the world.
He currently works as a biodiversity lead for Otago Regional Council.
Foulkes has put forward a radical manifesto including allowing trade unions to affiliate themselves to the Green Party, changing Te Tiriti o Waitangi to abolish the monarchy and making all essential services free.
He faces the prospect of campaigning against current favourite Chlöe Swarbrick, who was seen by some as the leading candidate to succeed Shaw.
Despite a torrent of online abuse, Swarbrick said that she was persuaded to run and has promised to work on delivering a Green-led government.
Despite recent electoral success the party has faced some damaging headlines after Golriz Ghahraman resigned as an MP following allegations of shoplifting from two high-end clothing stores.
Shaw has said he will remain in Parliament to support his Members Bill, which would insert a new clause into the Bill of Rights Act stating that everyone has a right to a clean, healthy and sustainable environment.
The bill was introduced to Parliament in December and is yet to have its first reading.
Nominations for the leadership contest close on February 14 and ballots would be sent on February 16.
Following policy conferences and party wide zoom calls branches will hold internal discussions with ballots to be returned by March 8.
The new co-leader will be announced on March 10.
