Microsoft files anti-trust complaint against Google

"The commission takes note of the complaint and, as is the procedure, will inform Google and will ask for its views on it," Amelia Torres, spokeswoman for EU competition commissioner Joaquin Almunia, said in a statement.

Microsoft's complaint feeds into an ongoing EU investigation into Google's market dominance, and follows similar steps taken by other companies - including Microsoft's German subsidiary ciao.de, an online shopping portal.

"We are not surprised by this step from Microsoft," Google spokesman Kay Oberbeck said in Hamburg. "We will continue the discussions with the EU Commission and thereby explain our business model," he added.

On Wednesday, Microsoft Vice President and General Counsel Brad Smith announced his company's initiative with a blog posting, where he listed six examples of anti-competitive behaviour by Google.

Among the allegations, Smith said that Google is preventing Microsoft's Bing search engine and Microsoft's Windows Phones from accessing videos from YouTube, which Google bought in 2006.

Smith acknowledged that there would "be some who will point out the irony" in Microsoft's actions, since over the last decade EU antitrust authorities fined the US company record amounts for shutting out competitors in the computer software market.