Google has backed down from its decision to conceal sexually explicit material on its Blogger service following an outcry from users about censoring their nude photos.

Just three days after saying the material would be banned from public Blogger forum sites, Google, faced with "a ton of feedback", said it would instead "step up enforcement" against commercial and illegal porn.

Google spokeswoman Katie Watson said the company does not disclose how many Blogger users it has, nor how many of them would have been affected by the policy change.

On Tuesday, Google warned Bloggers that from March 23, any site hosting nude pictures would be switched to private mode - only available to the authors and invited viewers. That ban came on the same day that social forum and news site Reddit said it would remove explicit photos, videos and links if the person pictured had not consented to the image being posted.

But in an online post yesterday, Google's Blogger said long-time users thought it was unfair to suddenly change the policy. The company was also swayed by users who said posting sexually explicit content was part of expressing their identities.

Explicit content on Blogger will still be marked by an "adult content" warning and Google's Blogger policy does not allow users to post nudes or sexually explicit images of someone else without that person's consent.

Mountain View, California-based Google bought Blogger in 2003. It was created by a company founded by Evan Williams, who would go on to co-found Twitter.

Blogging platforms have different approaches to porn and nudity. WordPress permits "mature content", but excludes it from public areas of the service and does not allow pornographic material such as "explicit sexual acts".

Photo-heavy Tumblr, now a part of Yahoo, says "sexual or adult-oriented content" must be flagged as "Not Suitable for Work" and does not allow for the embedding of sexually explicit video. Medium, also founded by Evan Williams, says flat-out: "No porn."