The government is being urged by a group of MPs to introduce a Kitemark system for ecologically friendly supermarket shopping bags and packaging.

The idea is being promoted by a cross-party alliance of Tory, Labour and Lib Dem MPs, who want retailers to be encouraged to come up with new and better ways of reducing Britain's plastic bag mountain.

It is estimated the UK uses 17.5 billion plastic carrier bags every year. Most are not biodegradable.

Headed by Tory MP Julie Kirkbride, the MPs are not calling for the UK to follow Ireland's example of a tax on every plastic bag issued.

Kirkbride, MP for Bromsgrove, said: "We are not looking for prescriptive or bureaucratic measures." and we're not talking about imposing a tax on every bag. But if individual stores want to follow the example, say of Ikea, by issuing biodegradable bags, which they charge for and then give the proceeds to an environmental organisation, that would be fine."