"I see the big challenge for this year in the still very tentative upturn," Mersch said in the text of a speech to be given at an Ifo Institute event in Munich. "The economic recovery in Europe still stands on wobbly legs."

Mersch also urged those countries which can afford it to invest in infrastructure.

While he did not specifically name Germany, it has faced criticism from countries in Europe and beyond for spending less on infrastructure over the past decade.

Government spending on this fell to 1.5 percent of gross domestic product (GDP) from 2 percent in 1999, and is well below the European Union average of 2.5 percent, according to the DIW economic institute.

Turning to small- and medium-sized businesses (SMEs), Mersch said that some of them suffer from bottlenecks in financing. He proposed founding a database which would assess SME credit risk.

Mersch repeated his call for increased use of asset-backed securities (ABS) as an SME financing tool.

"Robust European securitisation platforms could be a sensible addition to bank-based financing," he said.

(Reporting by Sakari Suoninen)