The dollar's recent rally ran out of steam on Friday as the yen gained on predictions that Japan's ruling Liberal Democratic Party would come out the winner in yesterday's elections. The dollar drifted down to ¥109.63 at 9pm GMT after ¥110.49 on Thursday.
The euro meanwhile edged up to US$1.2408 against US$1.2398 late Thursday in New York.
The currency market was confined to tight trading ranges, however, as uncertainties remained over the outlook for both oil prices and US interest rates in the wake of Hurricane Katrina.
"Markets are ending the week with a fair degree of uncertainty," Bank of New York currency analyst Simon Derrick said.
Fed Funds futures rates are pricing in two further interest rate hikes in the US by the end of the year.
But it was unclear whether the devastation wrought by Katrina will prompt the Federal Reserve to approve a pause in rate hikes this month.
"Early in the week there appeared to be a strong possibility that the Fed may pause at the next policy meeting to assess the economic fallout of Katrina," said Gregor Bush, economist at BMO Financial.
"Through the week however, comments from officials led investors to believe that the Fed is currently viewing this negative shock as transitory and is unlikely to deviate significantly from its previous course unless the economic data warranted such action," he said.
Higher rates would help the dollar by attracting more investment to dollar-based assets.
The greenback gained overnight as the market interpreted a speech late Thursday by San Francisco Federal Reserve Bank president Janet Yellen as mildly hawkish on rates.
In late New York trade, the US dollar stood at 1.2431 Swiss francs from SF1.244 on Thursday.
The pound was being traded at US$1.8392 from US$1.8353 late on Thursday.