By Maria Kiselyova
MOSCOW (Reuters) - Russia's competition watchdog said on Friday it had opened a case against Google Inc (NASDAQ:GOOGL.O) over alleged violation of anti-monopoly law, following a complaint from Russia's biggest search site Yandex NV over Google's mobile platform.
Yandex said on Wednesday it had asked the watchdog to investigate whether Google was abusing the dominance of its Android smartphone operating system, restricting competing apps.
"We have studied the complaint and decided to open proceedings regarding the violation of anti-monopoly regulation," a spokeswoman for the FAS competition watchdog said without elaborating.
The press service for Google's office in Russia denied anti-competitive behavior.
"Device makers are free to install the apps they choose and consumers always have complete control over the apps on their devices," Google said in emailed comments.
The Russian investigation comes after European regulators were said last July to be preparing a possible challenge to Google's mobile software business.
Two sources with direct knowledge of the matter said European regulators were laying the groundwork for a case centered on whether Google abuses the 80 percent market share of its Android mobile operating system to promote services from maps to search.
They said the European Commission had sent handset makers questionnaires asking whether there was a requirement set by Google that they should not pre-install apps, products or services on mobile devices that compete with Google software such as its search engine, app store and maps.
A Google spokeswoman said last year the company was committed to keeping Android open and that "anyone can use Android without Google, and anyone can use Google without Android."
Google is also under scrutiny in the United States, though a judge said in December she would require consumers suing Google over Android to submit more factual details in order for an antitrust lawsuit to proceed.