The yen appreciated vis-à-vis the U.S. dollar today as the greenback tested bids around the ¥93.35 level and was capped around the ¥94.30 level.  The yen strengthened across the board as traders were loath to assume too much risk during a period of decreased market liquidity.  Vice finance minister Tango reported G20 central bankers and finance ministers will discuss the global economy and regulation of the financial markets when officials convene in London next week.  Ongoing concerns that China will curb excess growth in the industrial sector continue to result in yen weakness.  China remains a major engine of global growth and a weakening in industrial activity could precipitate slower global growth, thereby decreasing demand for higher-yielding assets.  The repatriation of overseas yen assets back to Japan is also benefiting the yen.  On the political front, Democratic Party of Japan leader Yukio Hatoyama published an editorial that suggested Japan should work with other Asian countries to create a single regional currency and aspire to move toward regional currency integration.  It is likely that Hatoyama will become the next prime minister on 30 August if his Democratic Party of Japan defeats the long-incumbent Liberal Democratic Party.  There is growing speculation the Bank of Japan may extend its forecast for the end of deflation into early 2012 from early 2011, and this suggests the central bank will keep its ultra-easy monetary policy unchanged from quite some time.  The Nikkei 225 stock index lost 1.56% to close at ¥10,473.97.  U.S. dollar offers are cited around the ¥104.15 level.  The euro moved lower vis-à-vis the yen as the single currency tested bids around the ¥132.90 level and was capped around the ¥134.45 level.  The British pound moved lower vis-à-vis the yen as sterling tested bids around the ¥151.05 level while the Swiss franc moved lower vis-à-vis the yen and tested bids around the ¥87.30 level. In Chinese news, the U.S. dollar gained ground vis-à-vis the Chinese yuan as the greenback closed at CNY 6.8273 in the over-the-counter market, up from CNY 6.8266.  Chinese Premier Wen this week said the markets need to avoid being blindly optimistic about the global economic recovery and added China must maintain its moderately loose monetary policy and active fiscal policy.  PBoC has reported it will ensure reasonable and ample liquidity.