The dollar stayed on the defensive on Wednesday as investors got cold feet ahead of Federal Reserve Chairman Ben Bernanke's testimony to Congress later in the day.
Investors are wary of being long on the dollar after Bernanke last week caused a shakeout of positions with comments that were considered unexpectedly dovish.
"He probably does not want to knock down share prices. So he may want to avoid being too hawkish," said Koichi Takamatsu, a manager of forex at Nomura Securities.
The dollar index, which tracks the greenback's performance against a basket of major currencies, was not far from a three-week trough, having slid around 0.6 percent overnight.
It last stood at 82.639, 0.1 percent above late U.S. levels but still not far from Tuesday's three-week low of 82.395.
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That saw the euro pop back to $1.3140, down 0.15 percent on the day but still within sight of last week's peak of $1.3208.