The Bank of Japan will face a challenge if the yen weakens too far and the trend needs to be stopped, said Koichi Hamada, who's advising Prime Minister Shinzo Abe on choosing a new central bank chief. "It won't be easy," Hamada told reporters in Tokyo on Sunday, referring to decisions that the central bank would need to make on slowing monetary easing. He spoke after appearing with economic revitalization minister Akira Amari on an NHK TV show. Investors are gauging how far Japan may let the currency slide after Abe's pledges of aggressive fiscal and monetary action triggered a 10 percent decline against the dollar ... (full story)