Apple and Google may be battling for a piece of the nascent mobile ad market, but Facebook is happy to sit on the sidelines.FACEBOOK/

Despite the fact that more than one-third of Facebook’s 500 million users sometimes access the social networking service from a cell phone, Facebook does not currently show any ads to its mobile users.

And Facebook CEO Mark Zuckerberg says he’s not in any hurry to begin generating mobile advertising revenue.

“We only want to launch stuff that we think is really good and that can be a stable building block for us in the future. And I think we just need to see what makes sense for mobile advertising. But in the short term there’s no pressing need for us to monetize that immediately,” Zuckerberg said during a 30-minute interview with Reuters and the tech blog Mashable on Wednesday, after the launch of Facebook’s new Deals program.

Facebook mobile head Erick Tseng, who was also present, added that he didn’t think anyone has cracked the code on mobile advertising yet. “Slapping on a banner ad or some display ad on to a UI (user interface) especially when it a 3.7-inch display…it’s not really the greatest experience,” he said.