By | May 19 2010 6:31 AM

The Japanese yen and U.S. dollar strengthened against higher-yielding currencies after Germany imposed a ban on naked short selling to maintain stability in financial markets which aroused doubts that debt crisis in the euro zone will worsen. The dollar index, which tracks the dollar movements against six major currencies, edged up to 87.27 from the day's opening at 87.14 while it is expected to face resistance at 87.69.