They would also have to declare how much they raise each year from the levy and how the money is spent.
Writing in the Daily Mail today, prime minister Gordon Brown has backed the newspaper’s campaign.
He says: “We are looking at all this international evidence to see what steps we in Britain should take next…
“If Government compulsion is needed to make the change, we will take the necessary steps.
“We do not take such steps lightly – but the damage that single-use plastic bags inflict on the environment is such that strong action must be taken.”

