The dollar rose against the euro and Swiss franc on Wednesday as investors awaited more clues on the US interest rate outlook from speeches by Federal Reserve officials later in the day and US jobs data due on Friday.
The greenback was also pushed higher as sterling fell across the board following weaker than expected British manufacturing data.
But many investors are unwilling to take big positions ahead of speeches by Fed officials later and the non-farm payrolls data on Friday.
"Sterling's move probably did have an impact on the dollar. And as we head towards Friday the dollar should edge higher as (Tuesday's) employment component of the non-manufacturing ISM pointed to a higher than consensus number on Friday," said Gavin Friend, currency strategist at Commerzbank.
"The view from the Fed seems to be upbeat on the overall economy, mixed with a tinge of caution because of oil. But its upbeat stance and expectations for the jobs data should continue to keep the dollar in the ascendancy this week."
By 1130 GMT the dollar was up a quarter of a percent against the euro at $1.2283. Sterling slipped to a three-week low of $1.7773.
The greenback remained steady at 111.11 yen. It was also up a quarter of a percent against the Swiss franc at 1.2644.
Surging oil prices were keeping investors uncertain about economic prospects in oil-importing countries such as the United States and Japan.
Crude oil extended record-setting highs to $51.48 on Wednesday, led by worries over the impact of Hurricane Ivan on US winter fuel stocks. Prices are up more than 50 percent this year, driven by the strongest demand growth in a generation and a thin cushion of spare output capacity to deal with any unexpected supply outages.
Fed officials who spoke so far this week have been upbeat about growth prospects despite costly fuel.
Dallas Federal Reserve Bank President Robert McTeer said late on Tuesday he did not think oil prices posed a major threat.
Several Fed officials were due to speak later on Wednesday, including Federal Reserve Vice Chairman Roger Ferguson at 1600 GMT, Federal Reserve Bank of St. Louis President William Poole at 1700 GMT. Federal Reserve Bank of Kansas City President Thomas Hoenig was scheduled at 0045 GMT.
"Oil is really having a diminished impact on currencies. Maybe the market is taking on the message from policymakers that we have plenty of growth," said Steven Pearson, chief currency strategist at HBOS Treasury Services.