Google has hit back at Apple in the ongoing investigation into the lack of a Google Voice application being made available to iPhone users.

In a letter to the FCC last month, Apple denied refusing to certify Google Voice for use on the iPhone, saying the application was still under consideration. Google has now released sections of its evidence to the FCC in which it claims Apple did in fact reject the application.

“When we submitted our letter on August 21, we asked the FCC to redact certain portions that involved sensitive commercial conversations between two companies – namely, a description of e-mails, telephone conversations, and in-person meetings between executives at Google and Apple," said Richard Whitt, Washington Telecom and Media Counsel for Google in a blog posting.

“Shortly afterward, several individuals and organisations submitted Freedom of Information Act requests with the FCC seeking access to this information. While we could have asked the FCC to oppose those requests, in light of Apple’s decision to make its own letter fully public and in the interest of transparency, we decided to drop our request for confidentiality.”

The information states that Apple told Google it was rejecting the Voice application because it duplicated functionality already in the iPhone and it did not want applications that mimicked iPhone functions.

This contradicts Apple’s claims that the application was still pending and its concerns that Google Voice would confuse customers.

The case will now be decided by the FCC and will have important effects on the way the Apple App Store is run. If the FCC rules against Apple it could open the door to more applications that compete with Apple’s own systems.