Screengrab from video

Vienna - Prehistoric beauty won against 21st-century technology on Thursday when Facebook apologized for blocking an image of a nude statue considered one of the most important works from the Stone Age.

The social network had taken issue with an ad placed by Italian graffiti artist Laura Ghianda late last year that showed the "Venus of Willendorf," a small statue of a voluptuous woman that was created some 29 500 years ago.

"Our advertising policies do not allow nudity or implied nudity, but we have an exception for statues," a Facebook spokeswoman said.

"Therefore, the ad with this image should have been approved. We apologize for the error and have let the advertiser know we are approving their ad," she added.

"Venus" belongs to the Natural History Museum in Vienna, which considers the 11-centimetre-high statue its most valuable possession.

"We have invited Ms Ghianda to visit our museum if she happens to be in Vienna," museum spokeswoman Irina Kubadinow told dpa.

Kubadinow said she wasn't aware of anyone ever taking issue with the statuette's nudity since it was discovered in the early 20th century in Austria, she added.

It's not the first time that art has stirred a Facebook controversy.

Last year, the German city of Kassel discovered that its online photo gallery showing a nude Hercules statue had been blocked by Facebook.

However, rather than get into an argument with Facebook, city officials reposted the photo but digitally added a pair of red swimming trunks to cover up the Greek hero's buttocks.