Benoit Coeure, head of the Bank for International Settlements' (BIS) Innovation Hub, has described El Salvador's Bitcoin adoption as an "interesting experiment." Coeure is also a member of the BIS's executive committee.
“It’s an interesting experiment, indeed. I think we’ve been clear at the BIS that we don’t see Bitcoin as having passed the test as being a means of payment. Bitcoin is a speculative asset and should be regulated as such," the BIS told Decrypt via email.
Last week, El Salvador's president, Nayib Bukele, announced his aim to adopt Bitcoin as legal tender. Two days ago, El Salvador's Legislative Assembly approved the law that recognized Bitcoin as legal tender.
Coeure has previously written about CBDCs, digital innovation, and "the value of resilience and technology."

IMF Has a Problem With El Salvador’s Bitcoin Ambitions
The International Monetary Fund is taking issue with El Salvador’s recent move to make Bitcoin its second official currency. El Salvador’s president, Nayib Bukele, announced his plans for the Bitcoin law last week at the annual Bitcoin Conference in Miami; his bill was officially adopted yesterday, making El Salvador the only country in the world to require local merchants to accept cryptocurrency. “Adoption of Bitcoin as legal tender raises a number of macroeconomic, financial, and legal issue...
The head of the BIS's Innovation Hub may be intrigued, but just in March of this year, he said Bitcoin had failed the test on becoming a currency due to its volatile price. In addition, the IMF has a host of macroeconomic, financial, and legal concerns surrounding El Salvador's decision.