LONDON — Facebook's WhatsApp faces a complaint from European Union consumer groups who say the chat service has been unfairly pressuring users to accept a new privacy update in what it calls a breach of the bloc's regulations. 

The European Consumer Organisation, or BEUC, filed a complaint Monday over the way WhatsApp has brought in changes to its terms of service and privacy policy, saying they aren't transparent or easily understood by users. 

Many WhatsApp users switched to other chat apps like Signal and Telegram because of privacy concerns when the update was rolled out earlier this year because of concerns the changes would give Facebook access to more information on users. 

 "WhatsApp has been bombarding users for months with aggressive and persistent pop-up messages to force them to accept its new terms of use and privacy policy," BEUC Director General Monique Goyens said. "They've been telling users that their access to their app will be cut off if they do not accept the new terms. Yet consumers don't know what they're actually accepting." 

BEUC and consumer rights groups from eight member countries filed the complaint to the EU's executive Commission and the bloc's network of consumer authorities. 

WhatsApp said the complaint is based on a misunderstanding of the update's purpose and effect and would welcome the opportunity to explain it to the BEUC. 

"Our recent update explains the options people have to message a business on WhatsApp and provides further transparency about how we collect and use data," WhatsApp said in a prepared statement. "The update does not expand our ability to share data with Facebook, and does not impact the privacy of your messages with friends or family, wherever they are in the world."