The tension between Madrid and Catalonia's secessionists also stoked selling in the single currency after the Catalan parliament on Friday declared independence from Madrid following a secret ballot.

"The dovish surprise from the ECB was its openness to extend the duration of its bond purchase program," said Omer Esiner, chief market strategist at Commonwealth Foreign Exchange in Washington.

On Thursday, the ECB said it will extend its bond purchases into September 2018 while it will reduce its monthly purchases by half to 30 billion euros starting in January.

The move raised expectations the ECB would unlikely raise interest rates until 2019 as the U.S. Federal Reserve has remained on its path to hike U.S. rates further.

At 12:17 p.m. ET, the euro was down 0.6 percent at $1.1579, bringing its weekly loss against the dollar to 1.7 percent, which would be the biggest in 11 months.

Against the yen, the common currency was 0.6 percent lower at 131.93 yen after touching its weakest level in nearly two weeks.

The Catalan parliament vote revived some safe-haven demand for the yen and Swiss franc .

As the euro wobbled this week, the dollar strengthened on upbeat economic data, hopes for a tax-cut plan and speculation about President Donald Trump's selection of someone who favors a faster pace of rate increases than current Fed Chair Janet Yellen, whose term expires in February.

The U.S. government reported on Friday that the economy grew at a 3.0 percent annual rate in the third quarter, faster than the 2.5 percent forecast among economists polled by Reuters.

Earlier Friday, Bloomberg reported that Trump leans toward nominating Fed Governor Jerome Powell as the next Fed chief, but has not made up his mind.

The dollar pared gains briefly on that report as Powell is seen less hawkish than Stanford University economist John Taylor, another potential nominee to lead the central bank.

Trump is also considering Yellen, former Fed Governor Kevin Warsh and his economic adviser, Gary Cohn, for the Fed's top job.

Trump is expected to announce his candidate before a trip to Asia in early November.

The index that tracks the dollar against euro, yen and four other currencies <.DXY> was up 0.5 percent at 95.051 after hitting a three-month high at 95.150. The dollar index is poised for the biggest weekly rise so far this year.

 

(Additional reporting by Saikat Chatterjee in London; Editing by Dan Grebler)

By Richard Leong