The European Commission has asked Google for more information about its planned acquisition of Motorola Mobility, a step that is likely at a minimum to push back the day when the body would approve the deal.
The commission is also gathering reaction from those opposed to the $12.5bn purchase, which would combine the maker of what is now the most popular smartphone operating system with a main handset vendor.
Google has maintained that it is not interested in Motorola Mobility primarily for its patents, which it could use to defend other handset makers who use Android from legal challenges by Apple and others. But others fear that a close integration would give Google an unfair advantage over standalone hardware companies.
Brussels is already investigating Google on other grounds, such as whether its search results penalise internet competitors.
In a statement on Tuesday, Google said the request for more data was “routine” and that it was “confident the commission will conclude that this acquisition is good for competition”.