The dollar held steady above a three-year low, marking a fifth week of falls.
Sarah Hewin of Standard Chartered Bank says there is pressure on the ECB's Mario Draghi from hawks who want a tighter policy stance.
Philip Wee of DBS Bank says gains in the euro over the dollar may miss the "reality" that a stronger euro could impact the ECB's normalization path.
Daniel Gros, director of the Centre for European Policy Studies, speaks about the Germany economy and optimism in Europe.
Gold prices held near four-month highs on Wednesday even as a stronger dollar made bullion more expensive for holders of other currencies.
It would be "appropriate" for the European Central Bank to stop its bond purchases, Bundesbank head Jens Weidmann said in an interview.
Harry Colvin, director at Longview Economics, says markets are priced for tightening from the European Central Bank, but are likely to be disappointed.
The dollar held its modest losses on Wednesday, even as the Federal Reserve's latest Beige Book showed U.S. business activity was expanding.
Instead of euro strength, INSEAD professor Antonio Fatas says European politics are what could potentially derail growth in the region.
Europe eked out gains by Tuesday's close, however a downturn in commodities weighed on sentiment, despite positive trading from overseas.
The euro retreated as investors sold the currency on doubts that the ECB would back away from its pledge to keep buying bonds.
Gold fell on Tuesday from the previous day's four-month high.
The failure of Carillion was an isolated event, but still a big headache for the U.K. government, Will Hamlyn of Manulife Asset Management says.
Martin Lakos of Macquarie Wealth Management says a more hawkish ECB is just one factor in U.S. dollar weakness.
Phil Gronniger of Janus Henderson Investors says comments overnight by ECB governing Council member Ardo Hansson came a surprise to the market.
Catherine Yeung of Fidelity International says that all asset classes are doing well now, but a surprise to that picture could come if key central banks change views in the near term.
Sean Callow of Westpac Bank says he expects comments from the European Central Bank and the Bank of Japan at some point on recent dollar weakness.
Central banks in Europe and Japan are only adding assets at a slower pace when they trim purchases, says Marie Owens Thomsen of Indosuez Wealth Management.
Marc Franklin of Conning Asia Pacific says there is not a "great deal of visibility" on the U.S. dollar beyond the next few months.
The single currency is expected to strengthen over the foreseeable future as the European Central Bank (ECB) slows down its monetary stimulus, analysts told CNBC.