London (CNN Business) Mark Zuckerberg has put Facebook on a collision course with European regulators.

The CEO wrote Wednesday in a lengthy blog post that he plans to integrate WhatsApp, Instagram and Messenger, making it easier for users to communicate across the Facebook-owned platforms.

The plan is likely to run into stiff opposition in Europe, where sweeping privacy rules were imposed last year and regulators have already warned Facebook against sharing data between its companies.

In January, the Irish Data Protection Commission (DPC) released an unusual statement when the New York Times first reported that Zuckerberg wanted to unify the underlying infrastructure of the apps.

Ireland acts as Facebook's lead regulator in the European Union on issues of privacy because that's where the company has its regional headquarters. The DPC requested "an urgent briefing on what is being proposed" and said it would be "very closely scrutinizing" the tech company's plans.

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