It has now announced it will close collections on 31 March.
Approximately 5,000 gold, silver and bronze medals will be manufactured for the games.
Seven-time Olympic medallist gymnast Kohei Uchimura said he hoped the medal scheme would make people think more about their waste.
He said: “I think it is ‘mottainai’ [wasteful] to discard devices every time there is a technological advance and new models appear. In the field of sport, gymnastics techniques too have evolved as a result of the efforts made by athletes in the past.
“Tokyo 2020 Olympic and Paralympic medals will be made out of people’s thoughts and appreciation for avoiding waste. I think there is an important message in this for future generations.”
Gold and silver medals must contain a minimum of 92.5% silver, with gold medals plated with at least 6g of pure gold.Orginal Source