Tertiary Education Minister Steven Joyce is rejecting a suggestion that proposed restrictions on student loans are a case of age discrimination.
Mr Joyce has indicated that the eligibility for interest-free student loans will be tightened in the Budget on Thursday for students over the age of 55.
He has signalled they will be able to apply for loans to cover fees, but not living costs.
The Green Party says this is age discrimination and almost certainly a breach of human rights law.
But Mr Joyce says officials have looked into that and he is satisfied that such a change would be consistent with human rights legislation.
The key issue is the likelihood of students being able to repay their loans and that ability reduces as people get older, he says.