Japanese Finance Minister Taro Aso on Friday urged China to continue shifting its currency market towards a market-oriented system.
"Japan would face a tough decision on how to respond if China intervenes frequently in the market," he told a news conference after a regular cabinet meeting.
China devalued the yuan on Aug 11 as a slew of gloomy data, including soft exports and slumping wholesale prices, heightened concern over the strength of the world's second-largest economy.