Google is cracking down on cryptocurrency-related advertising.

The company is updating its financial services-related ad policies to ban any advertising about cryptocurrency-related content, including initial coin offerings (ICOs), wallets, and trading advice, Google's director of sustainable ads, Scott Spencer, told CNBC.

That means that even companies with legitimate cryptocurrency offerings won't be allowed to serve ads through any of Google's ad products, which place advertising on its own sites as well as third-party websites.

This update will go into effect in June 2018, according to a company post.

"We don't have a crystal ball to know where the future is going to go with cryptocurrencies, but we've seen enough consumer harm or potential for consumer harm that it's an area that we want to approach with extreme caution," Scott said.

Google's hard-line approach follows a similar ban that Facebook announced earlier this year.

While the crypto-currency boom has produced a lot of excitement and wealth, it's still a largely unregulated space and has spawned countless high-profile scams.

This news comes as Google releases its annual "trust and safety" ads report.

Google said it took down more than 3.2 billion ads in 2017 that violated its policies, which is nearly double the 1.7 billion it removed the year before.

Google parent company Alphabet makes roughly 84 percent of its total revenue from advertising, so convincing advertisers that its ecosystem is safe and effective is critically important.

[ Register or Signin to view external links. ]