Surging cryptocurrencies prompted two US financial regulators to weigh into the debate and warn about the risks to investors.

Bitcoin has been prominent in the news this week after the introduction of futures on the currency prompted it to rise further, when many had expected them to result in a mass shorting of the currency. Meanwhile, ethereum, the second largest cryptocurrency by market cap, rose by more than 30% yesterday to hit a record high.

Jay Clayton, chairman of the Securities and Exchange Commission, said: ‘Just as the SEC has a sharp focus on how US dollar, euro and Japanese yen transactions affect our securities markets, we have the same interests and responsibilities with respect to cryptocurrencies.’

At the same time J Christopher Giancarlo, head of the Commodity Futures Trading Commission (CFTC), warned that regulators have limited authority in these unregulated markets, the FT reported.

‘The relatively nascent underlying cash markets and exchanges for bitcoin remain largely unregulated markets over which the CFTC has limited statutory authority,’ he said.

In the UK, the Financial Conduct Authority has previously warned that some initial coin offerings (ICOs) could be scams, stressing they are ‘high risk, speculative’ investments.