The CBI banned the country's financial businesses from dealing in cryptocurrencies, including bitcoin. According to a press release by the Iranian state news agency, the CBI prohibited the use of cryptocurrencies within financial institutions, among concerns over money laundering.
"Virtual currencies have the option to be used for money laundering, supporting terrorism, and exchange of sums between wrongdoers," INRA said, quoting a CBI's circular. According to the circular, financial institutions must now avoid the sale or purchase of cryptocurrencies, as well as not take steps to promote them.
The press release states that the circular was based on a ban on cryptocurrencies passed by Iran’s anti-money laundering body in the last Iranian calendar year (which ends on 20 March 2018).