A complaint against Whakatane-based Te Whare Wananga o Awanuiarangi may be taken to the Serious Fraud Office.
Last month Awanuiarangi was accused of breaking the law and deceiving its students by calling itself a university.
Ngapuhi leader David Rankin raised concerns over the wananga using the words "indigenous university" when it wasn't a university.
He wrote two letters to Tertiary Education Minister Steven Joyce expressing his concern and wasn't satisfied with the response.
"If there's no clear rectification of this matter by the end of July, I'll pursue it through the Serious Fraud Office," Mr Rankin said.
Mr Rankin told Mr Joyce on May 11 he believed the Education Act had been breached, as an educational institution had called itself a university when it was not recognised as such.
"This issue is of concern, as I said, to our Maori students who are being misled into enrolling at an institution which calls itself a university, but is not."
The chief executive of Te Whare Wananga o Awanuiarangi, Professor Graham Smith, said they had received legal advice and were comfortable with the term indigenous-university.
"The term was all in lower case and hyphened so it makes a whole new word."
Dr Smith said that interestingly, universities could call themselves whare wananga if they wanted to.
Awanuiarangi was doing the same thing with good reason. Dr Smith said they had relationships with universities and indigenous people overseas and it was easier to define yourself as an indigenous-university than a whare wananga. He said Awanuiarangi was a whare wananga.
"That's what we are. We don't want to be a university."
Awanuiarangi runs courses from certificate to doctorate level and also has campuses in Whakatane, Auckland, Rotorua and Whangarei. Mr Joyce did not respond to inquiries on the issue.