Writing in the Daily Mail, he said ministers were prepared to take the “necessary steps” to reduce the number of carrier bags being picked up by shoppers.

In the article, published on Friday as part of the newspaper’s anti-plastic bags campaign, he said: “My approach is this: If we want others to change, we must make it easier for people to make the right choices.

“That applies to individual things each of us do, and also what our firms and shops do.

“So the Government is ready to do what it can to encourage a change in the way we use these bags.”

Mr Brown said Government was looking at schemes used in other countries, but his article did not offer any hints about what steps the UK Government will take.

In the article, published a day after M&S announced it would introduce a 5p levy on carrier bags in its food halls, he also praised retailers taking steps against bags.

The Conservatives chose the same day to release figures obtained through parliamentary questions showing that the Government has bought more than 1.2m plastic bags branded with logos and slogans over the past year.

More than £90,000 was spent on bags promoting departments such as the Department for Work and Pensions and state bodies such as the DVLA.

However, these revelations were swiftly followed by accusations of hypocrisy from the Liberal Democrats, who criticised the party for attacking its proposals for a plastic bag tax at the last general election.

Shadow Transport Secretary Norman Baker said: “When are they [the Conservatives] actually going to start coming forward with sensible ideas for cleaning up the environment?”

Kate Martin

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