Bitcoin, a virtual currency that allows users to exchange online credits for goods and services, will now be classed as a commodity in the U.S. along with gold and oil, according to the Commodity Futures Trading Commission (CFTC).

This decision follows a clampdown on unregistered firms which trade derivatives of the crypto-currency.

Bitcoins are not issued by any central bank, but they can be created online by using a computer to complete difficult tasks, a process known as mining.