The European competition watchdog is expected to charge Google with giving prominence to its own apps in Android licensing deals it strikes with mobile phone makers. Google generated an estimated $11 billion (€9.73 billion) last year from sales of ads running on Android phones featuring Google apps.

If the EU were to find Google guilty of market abuse it could lead to a fine of up to $7.4 billion or 10 percent of 2015 revenue, while forcing it to change its business practices.

EU antitrust chief Margrethe Vestager said on Monday her agency’s probe centers on the use of exclusive contracts which enable phone firms to run Google’s own apps and not necessarily on demands they bundle in a complete set of Google apps such as Search, Maps and Gmail and its Google Play app store on phones.

While Android is open source software, the vast majority of European phones run a standard package of software and Google apps that must be licensed from Google.

"Our concern is that by requiring phone makers and operators to pre-load a set of Google apps, rather than letting them decide for themselves which apps to load, Google might have cut off one of the main ways that new apps can reach customers," Vestager said at a regulatory conference in Amsterdam.

Last year, the EU charged Google with favoring its own shopping service in Internet searches. A decision on the shopping service case could come later in 2016.