Mana and the Internet Party are to announce on Tuesday morning whether they will form an alliance to contest the election in September.
The two parties have been in negotiations for several weeks over whether they should campaign together.
Mana leader Hone Harawira said his party had consulted its members and come to a clear majority decision.
He has been openly supportive of an alliance, but former MP Sue Bradford is one prominent member who has threatened to quit if an alliance is formed.
