Apple told federal regulators that it blocked the Google Voice program from running on the iPhone because it alters important functions on the device - yet Apple denied that it has rejected Google's application outright.

"Contrary to published reports, Apple has not rejected the Google Voice application, and continues to study it," Apple said in a letter to the Federal Communications Commission.

AT&T and Google also responded with letters to regulators on Friday. AT&T said Apple did not consult with the company before turning Google's program down.

Google kept confidential the parts of its letter describing Apple's reasons for rejecting Google Voice.

Google Voice gives people an additional phone number not tied to any one phone line. People can program the service to direct incoming calls first to a cell phone and then a work number and finally a home number. Users can set up voice mail and have Google Voice email transcripts.

It can also send text messages and place calls at low rates paid to Google, not the carriers. There is speculation that Apple and AT&T saw a Google Voice app for the iPhone as a competitor to their monthly plans.