Major supermarkets Sainsburys and Asda are backing a new smartphone app which enables shoppers to find and return missing shopping trollies.

Shoppers use the Trolleywise app, which is available from June 4, by photographing the trolley. The app then locates the trolley and alerts the supermarkets to collect it.

Supported by Trees for Cities and the River and Canal trust, the app is expected to help reduce the waste created by the 400,000 trollies that go missing every year out of the two million that are in circulation.

In addition, a tree is planted for every trolley retrieved.

It is hoped that the app will replace the current system in which local authorities have to collect the trollies and charge the finder’s fee back to the supermarket often through fines.

Environment Minister Lord de Mauley said: “Abandoned shopping trolleys are not only unsightly but have a real impact on the local environment. This innovative app will give shoppers and residents the chance to take swift action to tackle the thousands of shopping trolleys scattered around our streets or thrown in rivers and canals.”

Asda operations manager for retail service Neil Eccles said: “It’s a fantastic innovation and helps us and other retailers clean up the communities we serve.

A Sainsburys  spokesman added: We hope other retailers will follow our lead in recognising their responsibilities to the communities they serve and sign up to this scheme.”