If the U.S. government was concerned that the depreciating value of the US$ caused the Japanese government unstable, it would sell yen in the foreign exchange market. If successful the $/yen exchange rate would decline.
Step-by-step explanation:
Yen that would increase market yen supply and market dollar demand, which would stabilise the dollar price. $/yen means the number of dollars for yen that may be purchased.
This value will decline as the dollar begins to appreciate.
The average Nikkei 225 fell by 7.2 percent relative to its April point at 14 May. And, in April, the yen increased to 109-110 from 112-113 to the dollar. The fall of the stock market did not cause the yen to rise for the first time. As the following chart shows, Japan's stock market downturn has been strongly influenced since 2004 by a high yen as a result of the increase in stock prices.