According to an article from Iran, summarized in CoinDesk, it seems that the Central Bank of Iran may have agreed to a policy of working with digital currency exchanges in Iran to provide the connective banking relationships to facilitate international transactions of the movement of digital currencies and money in and out of Iran. One of the exchanges is this one.
Typically, the government of Iran works 24/7 to find ways to exit billions of dollars from Iran for its politically exposed persons and to buy goods and services, often through sanctions avoidance methods. The concern is that any use by Iran of digital currencies, especially mining activities, will help it move funds out anonymously anywhere in the world.
Concerns are heightened by the fact that digital currency exchanges have historically not applied or implemented sanctions laws to prevent transactions from Iran. For example, here is an article of a politically exposed person on a sanctions list who created a digital currency which a Canadian digital currency exchange is facilitating the sale of.
Older articles on Iran and digital currencies are here and here.