Introducing a digital euro would represent a "fundamental shift" in the eurozone's financial architecture, Governor Gabriel Makhlouf noted.
Eesti Pank found a blockchain-based solution could support an almost unlimited numbers of payments being processed at the same time.
The ECB has been discussing the potential launch of a eurozone central bank digital currency since the beginning of the year.
Smaller countries such as Greece, Latvia, Lithuania and Estonia would be hit the hardest.
Privacy is the number one thing Europeans want out of a digital euro.
In an interview with Bloomberg Wednesday, Lagarde said the digital euro will be rolled out within four years.
The digital euro project may get underway in mid-2021 after a period of review.
In a speech at a Reuters online event Wednesday, Lagarde said bitcoin was a "highly speculative" asset.
The Italian Banking Association said the work would help financial institutions prepare for the future.
The Bank of France’s deputy governor said there has been a “hands-on approach” with the bank’s experiment to launch a digital euro for the general public.
A Bank of America report on a possible mass-adopted digital euro noted that such movement could spell difficulty for commercial banks that could see some of their deposits migrate to the European Central Bank.
ECB President Christine Lagarde says the impetus for a central bank digital currency could come from the need to facilitate cross-border finance.
The "priority" research comes as Spain weighs a global pivot to digital economies.
Olli Rehn believes a digital euro "in one form or another" is all but inevitable.
How the firm helping lead Estonia's central bank digital currency research is approaching a mass-market crypto coin.