Mountain View (CA) - Google has reached a deal with radio giant Clear Channel to sell ads to radio channels via an online platform. The announcement comes on the heels of a similar deal Google struck with EchoStar to sell TV ad time.

Clear Channel owns 675 radio stations, more than any company in the US.  Under the multi-year ad agreement, around 5% of ad spots on Clear Channel stations will be set aside for Google to market and sell.

The online platform will be an auction-based system that opens up specific ad times to everyone.  It's the same kind of system that Google uses in its AdWords online ad selling infrastructure.

Along with TV and radio, Google has previously mentioned the possibility of selling newspaper ads.

Clear Channel owns radio stations in nearly every major market in the US, as well as 10 XM radio channels and 30 TV stations.