The head of Japan’s central bank on Thursday dismissed claims it is manipulating the yen to boost the country’s exports, the latest in a string of denials from Japanese officials.

“Our purpose is not to guide exchange rates, but to overcome deflation in the near-term and bring about sustainable growth with price stability,” Bank of Japan Governor Masaaki Shirakawa told a news briefing in Tokyo.

Tokyo has been on the defensive over aggressive monetary easing pledged by Prime Minister Shinzo Abe before he swept to power in December.

The issue is expected to top the agenda at a G20 meeting in Moscow on Friday amid growing concerns of a “currency war”. Shirakawa said he would reiterate Japan’s monetary policies were directed at boosting its limp economy, the world’s third largest, which led to the yen’s unintended steep slide.

The Group of Seven leading economies issued a statement on Tuesday in an attempt to cool rising anxiety but was also seen as a swipe at Tokyo.

“We reaffirm that our fiscal and monetary policies have been and will remain oriented towards meeting our respective domestic objectives using domestic instruments, and that we will not target exchange rates,” the statement read.

The yen has lost about 17% against the dollar and about 25% to the euro since November.