Apple has announced the purchase of mobile advertising firm Quattro Wireless.

News of the acquisition, which puts Apple in direct competition with Google in the mobile advertising market, came on the same day Google launched its Nexus One smartphone – a rival device to Apple’s iPhone.

The BBC reports that the value of the deal was not disclosed, but suggests it may be worth as much as US$275million (£170m).

Quattro sells advertising for the iPhone and Google’s rival Android devices, as well as other mobile websites and applications. The Massachusetts-based company’s client list includes the likes of Disney, Visa, and Ford.

Quattro is a direct competitor to AdMob, a company acquired by Google in November 2009 for $750million in the face of reported advances from Apple. The American Government’s Federal Trade Commission has been actively reviewing the AdMob acquisition due to concerns that Google could effectively monopolise the mobile ad market by leveraging its existing AdSense and DoubleClick programs.

Apple spokesman, Steve Dowling, said: “We look forward to developing exciting new opportunities that will benefit Quattro Wireless customers in the future.”