The yen is appreciating âtoo fastâ and speculators need to âbe carefulâ, Yasuo Fukuda, Japanâs prime minister, warned in an interview with the Financial Times on Monday. As the yen moved to an 18-month high of Y109.13 to the US dollar on Monday night, Mr Fukuda said: âIn the short term, yen appreciation would certainly be a problem. Any kind of sudden change in exchange rates would not be desirable.â While he stopped short of threatening Japanese intervention in the currency markets, Mr Fukuda said: âSpeculative movements need to be kept in check. What I am saying is: âBe careful, so that it [intervention] will not happen.ââ His remarks came shortly after Nobutaka Machimura, chief cabinet secretary, surprised some market participants by appearing to back the yenâs appreciation. âIt is wrong to think that Japan should object to the yenâs appreciation. In fact, I think a high yen is basically good for Japan.â http://www.ft.com/cms/s/0/a7a70b58-914c-11dc-9590-0000779fd2ac.html