The Finance Minister is warning property investors not to be tempted back into the housing market.
Bill English will not confirm if he is considering a capital gains tax on anything but the family home, but he told an accountants' conference the current tax system is unfair.
"I think there's concern about speculation in homes, that ordinary wage and salary earners who pay tax on every dollar get a bit concerned that the system allows some people to make large tax-free gains."
Any decisions on a possible capital gains tax or an increase in GST would be signalled in next year's budget.