“‘A debt ratio of 245pc of GDP is not really safe, and it is not happening because we are investing,’ said Takehiko Nakao, Japan’s ‘Mr Yen’ or vice finance minister in charge of the exchange rate.  Mr Nakao said the scope for further fiscal stimulus is running out and the country must restore public finances to a sustainable path by the middle of the decade.  The comments touch on an acutely sensitive topic. A number of global hedge funds and banks have begun “shorting” Japan’s debt, the world’s biggest at $23 trillion.  They are mostly taking positions through the credit default swap (CDS) market, betting that Japan will be the next big crisis theme.”