Prime Minister John Key says he would not support the Government imposing a charge on plastic bags from supermarkets.
Environment Minister Nick Smith has reportedly asked officials to investigate a scheme to charge about 5 cents for each plastic supermarket bag.
Mr Key said New Zealand's use of 1 billion plastic bags a year is excessive but he would prefer a voluntary, industry-led solution that shops such as Pak 'n Save and The Warehouse have introduced.
Mr Key said he was not aware of Mr Smith's suggestion, but would not support the Government effectively imposing a tax which went to supermarkets.
Green Party co-leader Russel Norman says putting a levy on plastic bags would have been a simple and effective way of cutting down on their use.