British savers might soon be able to invest in the controversial Bitcoin currency through a stocks and shares Isa.

The American regulator, the SEC, is about to decide whether to permit an "exchange traded fund", which would track the digital currency, to issue shares which would be traded on a US exchange.

If the fund gets the green light, British investors would be able to buy shares through their trading accounts and in theory even their Isa.

The investment fund has been proposed by the Winklevoss twins, the entrepreneurial pair famous for suing Mark Zuckerberg for allegedly stealing the idea for Facebook.

Exchange-traded funds work by pooling investors' cash and using it to buy the underlying assets - which in most cases are shares or commodities. Thousands of such funds exist, and investors can buy or sell through a broker just as if they were buying any other share.

Bitcoin traders are awaiting the SEC's decision with interest, predicting that if the fund is permitted, it will lead to a surge in demand from investors and thus a rapid rise in the currency's value - which has already risen substantially.

Bitcoin is generally regarded with suspicion by central banks and some governments. It is an unregulated currency in Britain, and its use banned completely in some countries, on the grounds that it is linked to money laundering and other criminal activities.