MADRID: Spain moved on Monday to regulate rampant advertising of crypto assets, including by social media influencers, tasking the stock market supervisor with authorising mass campaigns and making sure investors are aware of risks.

The rapid growth of cryptocurrencies and digital assets pegged to traditional currencies has drawn attention from regulators worldwide, who fear they could put the financial system at risk if not monitored.

The Spanish government said in its official bulletin advertisers and companies that market crypto assets will have to inform the CNMV watchdog at least 10 days in advance about the content of campaigns targeting more than 100,000 people.

The new regulations will start from mid-February and allow the CNMV to specifically monitor advertising for all types of crypto assets and to include warnings about risks involved in such investment.

The rules also apply to crypto-asset service providers when advertising their activities and to any person advertising on their own or on behalf of third parties.

These include influencers with more than 100,000 subscribers who are paid to advertise and promote crypto assets, the CNMV said in a statement, adding that they will have to pre-notify the watchdog of promotional posts and to warn of risks.

In November, the CNMV scolded soccer star Andres Iniesta after he promoted the cryptocurrency exchange platform Binance on his Twitter and Instagram accounts, telling him that he should be thoroughly informed about cryptocurrencies before making any investment in them or recommending others to do so.

Cryptocurrencies such as bitcoin have experienced high price volatility accompanied by a significant increase in aggressive advertising to attract investors.