A rise in the number of single-use carrier bags handed out by UK supermarkets has prompted renewed calls for a stricter levy on plastic bags in England.
The number of single-use bags handed out by UK retailers rose for the fourth year in a row in 2013 to more than 8.3 billion, figures show.
In England, the number of single-use bags from supermarkets rose 5% from just over seven billion in 2012 to 7.4 billion in 2013, the statistics from waste reduction body Wrap revealed.
Ministers have pledged to bring in a 5p levy for single-use plastic bags in England, although it will not come in until October 2015 and has prompted criticism because it will not include smaller retailers or paper bags.
The Government was forced to admit plans to also exempt biodegradable bags will not come in when the levy is introduced, because no such bag currently exists.
In the wake of the latest rise campaigners urged new Environment Secretary Liz Truss to drop the exemptions for small retailers and paper bags from the scheme in England.
Dr Sue Kinsey, spokeswoman for the Break the Bag Habit coalition - which includes the Campaign to Protect Rural England, the Marine Conservation Society and Keep Britain Tidy - said: "This further increase in bags given out in England underlines the importance of having a charge.
"However, to be as effective as the schemes in Wales and Northern Ireland, the exemptions for small businesses and paper bags must be removed.
"This increase should not come as a surprise to Government, as we pointed out the inadequacy of voluntary measures at the start of our campaign.
"Frankly, the charge should have been brought in sooner, and the advice of experts, retail organisations and environmental groups to remove exemptions from the charge should now be acted on."
Baroness Kate Parminter, co-chairman of the Lib Dem Defra Parliamentary Party Committee, said: "What these figures show is that there is still a huge number of these single-use plastic bags being needlessly wasted across the UK.
"Lib Dems had to fight tooth and nail to get the Tories to agree to the introduction of a levy, to cut wasteful use, with the excess money given to charity.
"Instead of jumping at the chance to cut the number of bags littering our towns and countryside, the Tories insisted on an exemption for household name convenience stores.
"Our policy will encourage reuse and recycling of plastic bags, curb unnecessary damage to the environment and dramatically cut the numbers that blight our towns, countryside and hedgerows."
Northern Ireland saw the number of bags handed out plummet by 71% as a carrier bag charge was introduced in April 2013, making it the only part of the UK to register a fall, the figures showed.
Wales saw an 18% increase last year, but its use of carrier bags is a fraction of other parts of the UK following the introduction of a 5p charge in the country. The number of bags handed out in Wales has fallen by 79% since 2010, the figures showed.
In Scotland, which is bringing in a levy this year, there was a 6% increase in the number of plastic bags handed out by retailers.
Across the UK as a whole, the number of single-use carrier bags provided to customers by supermarkets rose 3.2% between 2012 and 2013 and has risen more than a tenth (10.1%) since 2010.
But the number of single-use plastic bags handed out has fallen by 29% since the figures were first collated in 2006.
The number of reusable "bags for life" provided by retailers has almost doubled since 2006, up from 245 million that year to 424 million in 2013, the figures showed.
Welsh Minister for Natural Resources, Culture and Sport John Griffiths reminded shoppers in Wales to keep up the good work and to reuse their bags.
"People in Wales have adapted extremely well to our 5p carrier bag charge which was introduced in October 2011 and supermarkets across Wales are full of people reusing shopping bags.
"These latest figures show that consumption of carrier bag use in Wales has reduced by 79% since 2010, and this really is an excellent result. However, there is no room for complacency.
"Our 5p carrier bag charge really has had a significant impact on shopping habits across Wales and it is helping us to become a less wasteful society. I would urge everyone to keep up the good work and reuse bags whenever possible," he said.
A spokeswoman for the Environment Department (Defra) said: "Countries with the 5p charge have seen a dramatic fall in the number of plastic bags taken from supermarkets - that is why we are introducing a charge in England from October 2015.
"Our approach will help us reduce plastic bag usage and the litter they cause, while also protecting small and medium-sized businesses from any regulatory burdens at a time when the Government is supporting new growth in our economy."