Russia, chair of the Group of 20 nations, said on Wednesday it was important that Japan had not intervened on currency markets to weaken the yen.
"The Japanese yen was definitely overvalued," Deputy Finance Minister Sergei Storchak told reporters in Moscow, ahead of a meeting of G20 finance ministers and central bankers on Friday and Saturday.
Storchak, who is Russia's G20 finance 'sherpa', said developments should be monitored, but added that "there are no signs" that Japan's monetary authorities were intervening on the foreign exchanges.
"It would be an exaggeration to say that (Japan) is using the exchange rate as a stimulus for exports," Storchak said.
(Reporting by Lidia Kelly and Katya Golubkova; Writing by Douglas Busvine)