He said by using the precious metal, it could be used to evaluate the exports and imports activities among the East Asian countries.
"We can make settlement using that (new) currency (using gold). That currency must relate to the local currency as to the exchange rate and that is something that can be related to the performance of that country.
"That way we know how much we owe, how much we have to pay in the special currency of East Asia," he said during a dialogue session at the conference.
Dr Mahathir arrived in Tokyo on Thursday night for a three-day working visit