A week after Google (NSDQ: GOOG) said it would open its AdWords system to mobile users, it will now bring its pay-per-click ad program AdSense to cell phones as well, Reuters reported. The mobile expansion includes all the websites within the AdSense affiliate network. Google has been testing the system with a limited number of advertisers and publishers this year, and now it will open it to all mobile publishers in 13 countries, including the United States, Britain, France, China and India.

SEE ALSO: Google Includes AdWords In Google Mobile Search

The move is expected to give AdSense members a significant boost, as they’ll now be able to realize revenue when a mobile user clicks on their ad, which will consist mainly of text. The text ads will use the same auction model as the websites do; the ad messages will be aligned with the site’s content in mind and is intended to deliver an ad that’s designed to fit the interests associated with its users.

—NYT: Google has asked its AdSense members to restrict themselves to two ads per mobile page, as opposed to the looser limits for using AdSense on the web.

More here in Google’s Adsense official blogpost.