UPDATE 3-AT&T allows Internet voice calls on Apple's iPhone

"We are very happy that AT&T is now supporting VoIP applications," Apple spokeswoman Natalie Kerris said. "We will be amending our developer agreements to get VoIP apps on the App Store and in customers' hands as soon as possible."

Apple had previously not made Google Inc's (GOOG.O: Quote, Profile, Research) Voice application available for downloading on its iPhone. The two companies have bickered in recent statements to the FCC about why Google's Voice application is not available on the iPhone.

Google said Apple rejected it. But Apple said it is still studying it because the application alters the iPhone's telephone functionality and user interface.

AT&T's action, which is a reversal from a previous position to ban such calls on its 3G network due to revenue concerns, does not affect the Google Voice app spat.

The FCC, which has launched an inquiry into the state of competition, innovation and investment in the wireless industry, welcomed the move.

"When AT&T indicated, in response to the FCC's inquiry, that it would take another look at permitting VoIP on its 3G network I was encouraged," FCC Chairman Julius Genachowski said in a statement.

"I commend AT&T's decision to open its network to VoIP. Opening wireless services to greater consumer choice will drive investment and innovation in the mobile marketplace," he said.

On Oct. 22 the FCC is expected to propose a Net neutrality rule aimed at ensuring that network operators like AT&T and Verizon treat the flow of Internet content and applications without discrimination.

But the move by AT&T is not likely to deter the FCC from going ahead with the Net neutrality rule.