Half of the necessary bronze has been collected since recycling collection efforts began, but organisers still need twice as much silver.

It means officials are accelerating their efforts by installing new collection points at universities and post offices around Japan. 

The plan is for the metal to be collected from small electronic devices such as smartphones, due to Japan's status as a leading country in terms of the number of precious metals contained in such equipment. 

According to the Organising Committee, a total of at least 5,000 medals are required.

Silver and bronze medals are made almost entirely from pure silver and bronze.

Under International Olympic Committee rules, however, a gold medal must be made by using silver as a base material with at least six grams of pure gold plated onto it.

This means that about 10 kilograms of gold and about 736kg of bronze are needed for the Tokyo 2020 Games, along with approximately 1,230kg of silver, nearly double the amount of bronze.

As reported by Straits Times, a member of the Organising Committee said: "Just like the recycling of plastic bottles and empty cans, we aim to achieve a society where the separate collection of electronic devices is natural.

"To take advantage of the Tokyo Games to achieve this, we want to call for many people to cooperate with us."