"Some say we're doing too much in terms of monetary policy and we may be sowing the basis for prices to slip out of control," the Bank of Italy governor told an event at La Sapienza university.
"There are others, and I'm one of them, who say that the economic situation has worsened and we can't risk losing control of inflation expectations."
Visco said deflationary risks were unacceptable in particular in a situation of high private and public debt. Falling prices increase the value of debt in real terms.