"The dollar is having a bit of a pause ahead of Greenspan, but the yen was hit by growth data and sterling was affected by the apparently dovish (Bank of England) inflation report," said Tim Fox, market strategist at National Australia Bank in London.
At 1245 GMT the dollar was virtually steady on the day at $1.3030 per euro. On Tuesday it rose from a two-week low of $1.3052 after data showed foreign inflows into US assets were sufficient to cover the country's vast trade deficit.
But the yen traded some 0.7 percent weaker on the day at 136.86 yen per euro, after falling as low as 137.09, its weakest level since early January. It was also 0.6 percent down at 105.10 yen per dollar.
Japan's real gross domestic product declined 0.1 percent in October-December and revised figures showed it also shrank in the two previous quarters. It is the country's fourth recession in a decade.
And sterling lost about 0.6 percent against the dollar and the euro after the Bank of England said in its quarterly inflation report that risks to inflation and growth projections were "somewhat to the downside."
"The report is surprisingly dovish," said Marc Ostwald, strategist, Monument Securities in London.
Greenspan is due to testify on the US central bank's monetary policy before the Senate Banking Committee from 1500 GMT. He will give the second part of this twice-yearly testimony on Thursday.
Earlier this month, Greenspan caused ripples in financial markets after a speech in London where he sounded upbeat on prospects of a narrower US current account deficit, a key driver of the dollar's three-year decline.