Disposable coffee cups should be slapped with a 5p charge to cut down on the number of them being thrown away, the Liberal Democrats have suggested.
The Lib Dems want the Government to build on the success of the plastic bag charge, which was introduced in October last year and has prompted a more than 85% reduction in their use.
The party estimates that a similarly successful scheme targeted at takeaway coffee cups would mean more than two billion fewer being used every year, with people using reusable cups instead.
Some 2.5 billion disposable cups are thrown away in the UK every year and there are growing concerns about the relatively small number which are being recycled - estimated at fewer than one in every 400.
Lib Dem leader Tim Farron said: "Throwaway cups are a threat to wildlife and the environment and it's high time the Government stepped in to reduce the amount of waste created each year.
"I want to see a culture shift towards bringing your own cup for a refill, rather than buying cups which are often non-recyclable and then throwing them away.
"Liberal Democrats brought in the plastic bag charge and it's been proven highly successful - coffee cups are the next logical step."
The 5p charge will be piloted at the party's annual conference this September.
Ministers hinted in the House of Commons earlier this year that coffee cups could be taxed.
But the Government subsequently clarified the position and said there were "no plans" to do so.