The yen advanced modestly against a weaker greenback by the close of trade this week. The bulk of the losses for the dollar came on Monday when a sharp sell-off in risk assets fueled haven flows into the safety of the yen.

The Japanese yen was one of the best performing currencies on the week, as expected given the continued global shift to risk-aversion.

Risk aversion is heating up across financial markets as expected in the aftermath of last week's Federal Reserve monetary policy announcement after Ben Bernanke and company opted not to expand their balance sheet in the face of slowing economic recovery.

The British pound had a rough week, falling across the board against most of the major currencies.

The Japanese yen is virtually unchanged on the week with a marginal advance of 0.13% against the greenback. The currency has largely remained well supported despite a pick-up in risk appetite earlier in the week that saw investors chasing yields to the benefit of the aussie and the kiwi.

Another week of pronounced financial volatility produced sharp swings for the euro/US dollar exchange rate.

Traders seemed intent on finding the next weak link in the Euro Zone chain.

A cloud of uncertainty hangs over the financial markets after a tumultuous week of breakneck volatility was crowned by news that Standard and Poor's has lowered the United States' prized AAA sovereign credit rating.

The yen advanced against the greenback this week as traders sought refuge amid mounting concerns that the US may default for the first time in the nation's history.

The yen advanced more than 2 percent against the greenback this week as the dollar came under pressure on concerns over the looming debt limit deadline.