Deputy Prime Minister Nick Clegg says he hopes the money raised from the proposed 5p charge on plastic bags will be given to good causes.
The charge was unveiled at the Lib Dem conference today but government sources have acknowledged they are powerless to force retailers to hand over the money.
Clegg said: "We will discuss with retailers how the money raised should be spent but I call on them to follow the lead of industry in Wales and donate the proceeds to charity."
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