European Central Bank (ECB) chief economist Peter Praet said in an interview on Tuesday that there were "no taboos" in case of expansion of the central bank's asset-buying programme. He already used the phrase "no taboos" in November 2014 before the ECB announced its decision to introduce its quantitative easing.

Praet noted that a risk was growing that the inflation in the Eurozone will not reach 2% target by 2017.

"We are in a situation where the timeframe for achieving the inflation objective risks once again to be moved back. We will assess this in December, notably in light of the new macroeconomic staff projections," he said.