Jamie Dimon, chief executive and chairman of JPMorgan, has called the cryptocurrency bitcoin “stupid” and “dangerous”, and warned that if he caught a trader buying or selling it he would “fire them in a second”.

Speaking at the Barclays Global Financial Services Conference on September 12, the JPMorgan boss dubbed the currency a “fraud” and compared it to the Tulipmania during the Dutch Golden Age in the Netherlands, when prices for bulbs reached historic highs before collapsing in 1637.