Organisers of the 2020 Tokyo Olympics say metal from discarded electronic devices will be used in the production of the medals that will be awarded to athletes.
Japanese citizens are being asked to give the organising committee unwanted devices such as old phones and small appliances.
Organisers say the programme highlights the theme of sustainability and gives the whole nation a chance to participate in the preparations for the games.
The organising committee aims to collect as much as eight tons of metal which, after the production process, will result in two tons, an amount needed to produce 5,000 Olympic and Paralympic medals.
Collection boxes will be set up throughout the country. The collection will end when the eight-ton target is reached.