The Government is investigating whether to use overseas debt collectors to chase student loan repayments.
Loan debt now stands at more than $10 billion.
Revenue Minister Peter Dunne says billions are owed by people who have moved overseas and are not paying back their loans.
He says the situation cannot continue and using overseas debt collectors is one option being looked at.
Mr Dunne says loan debt could increase by $14 billion to $15 billion in the next few years if it is not reined in.
The Labour Party says it is fair to investigate ways to recover student debt but the Government needs to tread carefully.
MP Grant Robertson says he has concerns about using debt collectors in jurisdictions where the New Zealand Government won't have much control over their activities and where there will potentially be increased recovery costs.