Facebook has started displaying ads in its users News Feeds on desktop based on their browsing habits outside of the platform.

Until now, this type of targeted ad delivered from the Facebook Exchange (FBX) could only appear on the right hand side of the page, with sponsored stories in the news feed limited to brands liked by friends. The pilot for these ads started with a limited number of users today.

When quizzed about when these ads might come to a handset near you, Facebook said it was focusing on where they had already seen success with targeted advertising.

A spokesperson said: “Facebook is currently focused on building out a solution for desktop, since it’s much more in line with what FBX has been doing effectively in the right hand side. Facebook has also found that desktop is where more people respond to FBX targeted ads and link offsite to investigate further and potentially purchase something.”

The company has been fighting claims from brands this week that changes to its EdgeRank algorithm mean full-blown mobile ads are taking priority over and reducing the reach of organic branded content. Facebook has denied this.