Google plans to censor unauthorised nude photos from its influential internet search engine in a policy change aimed at cracking down on the malicious practice known as "revenge porn".

The new rules will allow people whose naked pictures have been posted on a website without their permission to ask Google to prevent links to the image from appearing in its search results.

A form for submitting the censorship requests to Google should be available within the next few weeks.

Google has traditionally resisted efforts to erase online content from its internet search engine, maintaining that its judgments about information and images should be limited to how relevant the material is to each person's query.

That libertarian approach helped establish Google as the world's most dominant search engine, processing about two-thirds of all online requests for information.

The Mountain View, California, company decided to make an exception with the unauthorised sharing of nude photos because those images are often posted by ex-spouses, partners in a broken romance or extortionists demanding ransoms to take down the pictures.

"Revenge porn images are intensely personal and emotionally damaging, and serve only to degrade the victims - predominantly women," Amit Singhal, Google's senior vice president of search, said in a blog post.

Laws against revenge porn have already been passed in at least 17 US states and a national ban is expected to be introduced in Congress this year.

Google's stand against revenge porn will not necessarily purge it because not even the internet's most powerful company has the authority to order other sites to remove offensive or even illegal content. But Google is hoping revenge porn will prove less mortifying to its intended victims by making it more difficult to find.

Other heavily-trafficked sites, including Twitter and the social forum Reddit, have embraced policies banning nude photos from being posted without the subject's permission. Earlier this year, Google tried to prohibit sexually-explicit material from the publicly accessible sites in its Blogger service only to reverse itself within a few days amid cries of unwarranted censorship among Blogger's users.

It is not the first time Google has excised sensitive content from its search index. In most instances, the company has been forced to do so under laws imposed in various countries where it operates.

While its search engine operated in mainland China from 2006 to 2010, Google blocked information that the country's communist government deemed to be inappropriate and the company has been scrubbing humiliating information from people's pasts in Europe for the past year.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.