"QE (quantitative easing) will not last forever", Coeure said on the sidelines of the World Economic Forum in Davos, Switzerland. "It's too early to start a discussion on tapering."

On Thursday, the ECB decided to keep its policy stance unchanged, wanting to see further improvements in growth and inflation. In December, it scaled down its monthly purchases by a quarter to 60 billion euros (51.8 billion pounds) from April but extended the programme until the end of 2017.

(Reporting by Andreas Framke; Editing by Balazs Koranyi)