Google is banning pornographic adverts from appearing on its search engine.

The changes, which took effect on Monday evening, prevent any advertising that features feature “graphic sexual acts with intent to arouse including sex acts such as masturbation”, according to CNBC.

A company spokesman told the network that Google gave notice that it would be implementing restrictions on its AdWords service back in March, thereby providing advertisers with time to research other avenues.

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An email sent to advertisers in June said: “Beginning in the coming weeks, we'll no longer accept ads that promote graphic depictions of sexual acts including, but not limited to, hardcore pornography; graphic sexual acts including sex acts such as masturbation; genital, anal, and oral sexual activity.

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“When we make this change, Google will disapprove all ads and sites that are identified as being in violation of our revised policy. Our system identified your account as potentially affected by this policy change. We ask that you make any necessary changes to your ads and sites to comply so that your campaigns can continue to run.”

“Porn” is one of the most popular searches on Google: in May alone, there were almost 351 million searches for the terms “sex”, “porn”, “free porn” and “porno”.

The policy changes have led to speculation that Google will completely change the way in which it relates to porn.

Michael Fattorosi, an attorney with Fattorosi & Associates, a boutique firm that represents the adult industry, told CNBC: “This is another example of a mainstream company turning its back on the industry that has supported it.

“The question now becomes: Will they block adult content from their search results?”