Morocco's currency regulator has announced a ban on transactions in bitcoin and other virtual currencies, in a country where foreign exchange flows are tightly controlled.

"Transactions via virtual currencies constitute a breach of regulations, punishable by penalties and fines," the Offices des Changes said in a statement on its website.

The announcement came a week after Moroccan digital services company MTDS said it would accept payment in bitcoin.

MTDS said it was the first time the regulator had taken a clear position on bitcoin payments.

MTDS head Karl Stanzik said the company had dropped its proposal in order to "comply with Moroccan law" but that it would be "very difficult to control" bitcoin transactions due to the currency's secretive nature.

Unlike physical currencies, bitcoin and other so-called crypto-currencies are not backed by states or regulated by central banks.