"The (bond) purchases will be ended gradually rather than abruptly, ensuring a smooth transition of sufficient length," Vasiliauskas said in the Eurofi magazine.

"Any further policy steps will be well-discussed, data-based and gradual, providing sufficient time for markets to adjust," he said. "We should be ready for an increase in market volatility, which has been exhibiting unnaturally low levels."

Vasiliauskas said that the ECB Governing Council has already built an agenda for its next several steps, spanning an extended period of time.

Copyright Reuters, 2018