The decision on whether to allow credit card users to buy cryptocurrencies is a credit risk decision made by the card-issuing banks, a spokesman for Mastercard said Banks in Britain and the United States 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. Lloyds Banking Group Plc, Britain's biggest lender, said on Sunday it would ban its credit card customers from buying cryptocurrencies, following the lead of US banking giants JP Morgan 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. Concerns have arisen among credit card providers because their customers have increasingly been using credit cards to fund accounts on online exchanges, which are then used to purchase the digital currencies. H...