Come on Britain, why not follow Uganda's example and banish plastic bags?? They're made from oil, they don't biodegrade, they litter the streets, countryside, rivers and seas. They poison the soil and choke animals, birds and marine life.
I confess to feeling slightly righteous about this. Most French supermarkets have already stopped handing out free plastic bags. You have to bring your own (most people have those bag for life ones), or plastic or cardboard boxes. I've already covered that subject in more depth here.
Do something positive, next time you're at the supermarket, don't grab all the free bags (you probably take far more than you need anyway - you know you can carry more than a loaf of bread and a punnet of strawberries in one bag?). Buy a bag for life and remember to take it with you on future trips.
You don't need the throw-away plastic bags. Because that's what happens to them - they get thrown away and finish up scarring the land. They make the whole country look like a tip, strewn along motorway verges and blowing around high streets. BAN THE BAGS.