Clarity on crypto rules in "onshore" locations such as Britain and the United States is needed otherwise crypto firms will develop "offshore," the chief executive of major U.S. crypto exchange Coinbase Global Inc said on Tuesday. Asked about the failure last year of the Bahamas-based FTX exchange, Brian Armstrong told a conference in London: "This is the reason why we need clarity about legislation and regulation onshore because if the UK doesn't have this, if the US doesn't have this, these firms are going to be built in offshore havens."