Winston Peters says New Zealand First wants to limit foreign ownership of residential property, and ban foreign boats and crews from fishing New Zealand waters.
Mr Peters told TV3's The Nation he would not "stand around while somebody from off shore with 77 homes, and has now become a major landlord in Auckland and filtering in, and gauging money out of our economy".
Asked whether that would drive property prices down by reducing demand, he said some demand was of no use to New Zealand.
"I live in an area where the house prices have gone up 114 per cent. Now you can't save that fast and I can't, and there's not many people watching this programme that can save that fast. So where does a young family fit into this country? They haven't got a hope in this context."
Mr Peters said New Zealand wanted to see the "New Zealandisation" of the fishing industry.