EU competition regulators have extended their investigation into Alphabet unit Google's deal for fitness tracker maker Fitbit to December 23, the European Commission said today. 

The EU competition enforcer last month kicked off a full-scale probe into the deal, saying Google's pledge not to use Fitbit's data for advertising purposes was insufficient to address competition concerns. 

"The Commission extended the deadline in agreement with the parties," the EU executive said in an email. 

Google has said the combination of its and Fitbit's hardware would boost competition in the sector where players include Apple, Samsung, Xiaomi, Huawei and others.