The Tories have highlighted the growing problem of litter blighting the UK's motorway network, with 50,000 bin bags worth a year of rubbish strewn around one motorway alone.
Around 300,000 bags of rubbish have been collected from the M25 and its link roads in the past five years, according to figures from the Highways Agency obtained by the Conservatives.
And the total collected from the UK's motorway network as a whole probably amounted to around 700,000 bin bags worth of litter and fly-tipping, the Tories said.
There are no overall figures for how much the clean-up costs, but the Highways Agency said that collecting rubbish from the M6, M1, M69 and M42 in the West Midlands cost £167,000 a year.
Peter Ainsworth, the shadow environment secretary, said: "It is shocking that every few yards you could fill a skip full of rubbish with the amount of litter being dumped on our roadsides.
"A small number of people are trashing our environment, using public spaces like rubbish bins and chucking litter without any care for where it ends up."
He added: "These are just the latest batch of depressing figures which show that Britain is groaning under unacceptable levels of litter."
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