​Bitcoin has no fundamental value and is likely to end in tears once speculators discover how hard it can be to extricate their cash, Singapore's financial watchdog has warned.

Sopnendu Mohanty, fintech chief for Singapore's monetary authority (MAS), said there was a crucial difference between Bitcoin and rival cryptocurrency Ethereum, but it was far from clear whether either improved day-to-day transactions or had much potential as a tool for central banking.

"Bitcoin has no natural intrinsic value. Can you buy a house with it? Can you use it for daily interactions? It may be valued at $US18,000 ($23,477) right now but what I want to know is how you convert it into fiat currency and realise that value. The risk comes at the moment of conversion," he told London's The Daily Telegraph.

The lapidary verdict on the Bitcoin craze carries some weight. Singapore's city-state is the leading fintech hub in Asia. The MAS is currently carrying out the most far-reaching research into blockchain and distributed ledger technology by any central bank or monetary authority in the world.