The Māori Women's Welfare League has set up an inquiry into the activities of some of its branches affiliated to the Destiny Church.
The inquiry will look at whether branches set up by the church headed by Brian Tāmaki have breached the non-sectarian nature of the league and its constitution.
The wife of the church's leader, Hannah Tāmaki, is seeking to become the president of the league.
However, the league has put church enrolments and Mrs Tāmaki's nomination on hold.
League member Prue Kapua told Checkpoint she is opposed to any church leader becoming president, as the league would start to be perceived as a sectarian organisation.
A spokeswoman for Mrs Tāmaki says only 300 Destiny members had enrolled in the league up till mid-June and some had been members for several years.
Mrs Tāmaki has hinted she will go to court if necessary to get her name on the ballot papers.
The league says the inquiry will be carried out in private by its general manager, lawyers and accountants and should be completed by the national conference in August.
The Māori Women's Welfare League was founded by Dame Whina Cooper in 1951.