CANBERRA (XINHUA) - A ban on single-use plastic bags by Australia's two biggest supermarket chains has prevented 1.5 billion bags from entering the environment in less than half a year.

The National Retail Association (NRA) on Monday (Dec 3) revealed that the consumption of single-use plastic bags has dropped 80 per cent since Coles and Woolworths stopped distributing the bags in late July.

The decision was met with anger from some Australian shoppers, but Mr David Stout, the manager of industry policy at the NRA, said the new figures justified the "brave" decision by the major chains.

According to the manager, Woolworths and Coles - whose parent companies Woolworths Limited and Wesfarmers are Australia's two biggest companies by revenue - had paved the way for small businesses to follow their lead.

"They're obviously seen as the product stewards so a lot of people will come back to them," the manager told the Australian Associated Press (AAP).

"Obviously the best thing for smaller businesses is to either engineer out the bag completely or have the customer pay. They should be able to consider that strategy without fear of backlash," the manager said.

"Everyone delivering things in a package need to take responsibility for what they deliver it in. I think there's going to be a lot more pressure on all of us to be more aware of what we consume," the manager added.

Rather than giving out single-use plastic bags for free, the two supermarkets now advise shoppers to bring their own reusable bags or make them purchase reusable bags.

Australia has legislated to phase out single-use plastic bags in every state and territory, except for New South Wales, the nation's most populous state.