Regulators in the Netherlands and Canada say the popular messaging application WhatsApp is violating internationally accepted privacy norms by stockpiling phone numbers belonging to people who don't even use the service.

Officials in both countries say WhatsApp Inc. is going through its users' address books and copying every single phone number before transmitting them to the Mountain View, California-based company's servers.

Many communications services ask for access to their customer's address books to help connect them with friends. But under Canadian and Dutch law, personal information belonging to nonusers must be destroyed once it's no longer being used.

Canada's Office of the Privacy Commissioner and the Dutch Data Protection Authority also criticized WhatsApp for weak security and sloppy encryption.

Emails and Twitter messages sent to WhatsApp weren't immediately returned.