The Bank for International Settlements (BIS) and the central banks of France, Singapore and Switzerland have completed a joint experiment testing cross-border trade and payments of wholesale central bank digital currencies (CBDC). Banque de France published the report on September 28.

The so-called Project Mariana was developed by the Banque de France, the Monetary Authority of Singapore and the Swiss National Bank under the auspices of the BIS. Using decentralized finance (DeFi) technology concepts on a public blockchain, it tested cross-border trading and payments of hypothetical euro, Singapore dollar and Swiss franc CBDCs between simulated financial institutions.

The concept works by using a common token standard on the public blockchain, bridges for the seamless transfer of CBDCs between different networks, and a specific type of decentralized exchange to automatically trade and settle spot currency transactions.

According to the statement, although the participants found the experiment successful, they state that "more research and experiments are needed." He also makes a reservation about the experimental nature of Project Mariana, stating:

“Project Mariana is purely experimental and does not indicate that any of the partner central banks are considering issuing CBDC or approving DeFi or any specific technological solution.”

The day before the release of Project Mariana, BIS director general Agustín Carstens spoke about the need to clarify national legal frameworks in countries where central banks do not have the right to issue CBDCs.

BIS remains a major supporter of cross-border CBDCs, and several pilot tests are being conducted around the world. In September, as the central banks of Hong Kong and Israel published the results of Project Sela, Hong Kong Monetary Authority CEO Eddie Yue announced the expansion of Project mBridge involving the central banks of China, Thailand and the United Arab Emirates.