The business practices of US big tech firms are under close scrutiny across Europe over concerns about privacy, with huge fines handed out in recent years.
The Norwegian watchdog, Datatilsynet, said Meta uses information such as the location of users, the content they like and their posts for marketing purposes.
“The Norwegian Data Protection Authority considers that the practice of Meta is illegal and is therefore imposing a temporary ban of behavioural advertising on Facebook and Instagram,” it said in a statement.
The ban will begin on August 4 and last three months to give Meta time to take corrective measures. The company will be fined one million kroner ($100,000) per day if it fails to comply.
Meta spokesman Matthew Pollard was quoted as saying by Norwegian public radio channel NRK that the company will review the demands and that the announcement will not have an immediate effect on its activities.