Japan’s foreign exchange markets have lost 5.5 percent since June 3.
That’s the worst monthly decline since May.
On Wednesday, the Japanese central bank announced that it would extend the foreign exchange buying ban from March 28 to April 24.
The bank also said that it will extend its foreign exchange purchases from March to April to support economic growth.
Japan’s currency, the yen, has fallen nearly 1.4 percent against the dollar since June.
The yen is now trading at around 71.5 yen, its lowest since mid-2013.
The yen has lost more than 70 percent of its value against the greenback since its November peak of more than 60.5 against the U.S. dollar.
The Nikkei 225 is up almost 3 percent over the past 24 hours, while the Hang Seng index of mainland Chinese shares is up nearly 8 percent.
A key reason for the weakness is that many investors believe that the U:C.O.E. stimulus will not produce the expected output boost, according to Kenji Yoshida, a former finance minister in the ruling Liberal Democratic Party and the former president of the Bank of Japan.