Energy Minister Gerry Brownlee says producing oil domestically will reduce environmental costs.
Oil exploration companies are this summer sinking seven wells - the most ever - in search of undersea oilfields off the New Zealand coast.
But the Green Party says creating more carbon dioxide by burning fossil fuels such as oil flies in the face of efforts to reduce greenhouse gases.
However, Mr Brownlee says much of the oil used in New Zealand is imported, which carries an environmental cost that would be lessened if oil was sourced domestically.
He says he does not understand the environmentalists' problem with that.