Banks in Britain and the US have banned the use of credit cards to buy bitcoin and other "cryptocurrencies", fearing a plunge in their value will leave customers unable to repay their debts.
Bitcoin staged a spectacular rise in value, reaching a peak of US$19,187 on December 16 on the Luxembourg-based Bitstamp exchange.
But the biggest and best-known cryptocurrency has since fallen dramatically and according to Bloomberg is down 20 per cent in the last three days to US$6857.
Lloyds Banking Group, which issues just over a quarter of all credit cards in Britain, and Virgin Money said they would ban credit card customers from buying cryptocurrencies, following the lead of US banking giants JPMorgan Chase & Co and Citigroup.
The move is aimed at protecting customers from running up huge debts from buying virtual currencies on credit, if their values were to plummet, a Lloyds spokeswoman said.