The Scottish Government should quickly establish a bottle return scheme to help reduce litter in the countryside, outdoor groups have said.

The project is aimed at encouraging people not to throw away their empty bottles and cans.

Under the scheme, shoppers would pay a deposit which would be handed back to them once the container is returned.

Outdoor groups including surfers, kayakers, cyclists and ramblers have written a joint letter to the environment secretary Roseanna Cunningham calling on her to act swiftly as the country's "extraordinary wild places" are "too often spoilt by empty cans and bottles".

In the letter, the groups said: "Although all empty drinks containers are unsightly in our natural environment, we share a particular concern about littered plastic and glass bottles.

"We are runners, cyclists, swimmers, horse riders, mountain bikers, kayakers, surfers, rafters, mountaineers, ramblers and educators.

"For every one of us, broken glass poses a direct threat to us, our learners or to our equipment or indeed to our horses."

It added: "We know that the problem is getting worse every year and we also know about the benefits deposit return systems have brought elsewhere in terms of a sharp reduction in litter.

"We would therefore urge you, as the responsible minister, to move quickly to establish a system of this sort for Scotland."

A Scottish Government spokesman said: "The Scottish Government is considering the benefits and drawbacks of a deposit return scheme.

"Such a scheme has the potential to reduce litter and improve recycling but other factors must be taken into consideration.

"These include the impact on small stores with limited space, costs to retailers and the impact on local authority kerbside collections."