Japan might be talking up the yen by saying less about it, the lack of information adding to the sense of uncertainty and putting traders on the back foot.

“It seems to me that the government may be changing its approach to FX intervention,” said Norihiro Yamaguchi, an economist at Oxford Economics, using market shorthand for foreign exchange.

Japan’s currency is now trading near its weakest levels in 40 years against the dollar. For a while, officials issued clear threats. Now, they are saying little or nothing.