Eurozone data released earlier showed improved economic sentiment for the fifth month in a row in October. Also, inflation in the 12-nation currency area fell less than expected to 2.5 percent in October from 2.6 percent in September, European statistics agency Eurostat said in its first estimate.
The interest rate futures market has priced in a rise in the ECB refi rate to 2.25 percent by March and players are speculating that the cost of borrowing could rise before the end of the year.
"There's a gradual feeling that the ECB is closer to raising rates than first thought," Bank of New York currency strategist Neil Mellor said.
ECB Governing Council member Nout Wellink said on Friday that the ECB is increasingly worried about high energy costs and sometimes words are not enough for central banks to contain price pressures.
Other ECB speakers due later in the day include President Jean-Claude Trichet.
"Speculation regarding a ECB rate hike is likely to start building further, especially coming on top of the more hawkish comments we have been seeing from the ECB officials, so that will be euro supportive," BNP Paribas senior foreign exchange strategist Ian Stannard said.
By 1129 GMT, the euro was up 0.10 percent at $1.2150 after rising 0.6 percent on Thursday. The common currency was fetching 140.02 yen, in sight of the previous day's six-month high of 140.20 yen.
Stannard said euro/dollar could move initially up to the $1.2205 area before going into a $1.2260/1.2300 range.
The dollar was down 0.16 percent on the day at 115.24 yen, moving further from Thursday's two-year high above 116 yen.
"We have had disappointing data in the United States this week and in the euro zone we have had comforting news," said Niels Christensen at Societe Generale in Paris. "If we get a weak GDP number no one would want to hold onto long dollar positions next week."
The US economy was seen growing 3.6 percent in the third quarter, up from 3.3 percent in the previous quarter, according to a Reuters poll. The data is due at 1230 GMT.
Traders said the yen got a lift from a Financial Times report that US Treasury Secretary John Snow had told China's leaders that Washington wanted to see another revaluation of the yuan before President George W. Bush visits Beijing next month.
The yuan hit a new post-revaluation peak of 8.0846 per dollar, up just 0.3 percent since China revalued on July 21, the same amount as its theoretical one-day trading band.
Any strengthening of the yuan is expected to spill over into other Asian currencies.