The yen has been selling all week. Its latest bout was initially catalyzed by Yellen's comments suggesting that more interest rate hikes were likely later this year. The yen further weakened after Trump's tax reform plans were announced on September 27. While North Korea remains in the background, tensions have recently abated thanks to conciliatory remarks by the Trump administration. Within Japan, Abe has dissolved the Lower House today and announced a snap election. While initial polls suggest that his party is most likely to win, the election introduces some uncertainty to the currency.
USD/JPY is currently trading above 113, having risen from below 112 earlier in the week. EUR/JPY has been trading sideways since Tuesday, after falling sharply following last weekend's elections in Germany. The pair is currently trading close to 132.60.
This week, markets will be closely watching inflation data that is set to be released on Friday. Japan has been mired in low inflation for several decades, and most observers expect the current trends to continue. If the status quo is maintained, inflation data should have a minimal impact on the yen.