"It may be worth exploring the establishment of a truly European issuance service – at least for some supranational debt instruments," Mersch told a conference. "We could even think about the ECB/Eurosystem playing an active role in setting up such an issuance service."

Mersch added that the ECB could even consider using blockchain technology, originally developed for the bitcoin virtual currency, which uses a decentralised networks to verify transactions, reducing the need for intermediaries, lowering costs and speeding up transactions.

(Reporting by Balazs Koranyi; Editing by Robin Pomeroy)