EXCLUSIVE: Japan top FX diplomat urges markets to heed 'very clear' warning on yen ↧ ↧ EXCLUSIVE: Japan top FX diplomat urges markets to heed 'very clear'... Japan's top currency diplomat Atsushi Mimura said on ​Monday markets should take at face value the "very ‌clear" message Tokyo and Washington delivered last week on the yen, signalling his resolve to act against excessive falls ​in the currency.