Apple has claimed that opening up iPhone NFC chips to mobile banking use outside of Apple Pay would compromise the phones security.

The claim follows four Australian banks requesting permission to negotiate with Apple as a bloc rather than join Apple Pay. The banks – the Commonwealth Bank of Australia, Westpac, National Australia Bank and Bengido and Adelaide Bank – were petitioning for their own apps to be able to use the iPhones contactless ability and therefore access a portion of the transaction fee that Apple takes.

According to The Register, the banks petitioned the Australian Competition and Consumer Commission (ACCC) to be able to approach Apple as a bloc, and the ACCC posted Apples reply to the submission on its website.

Apple claims that its security measures for both hardware and software are so deeply integrated that providing access to the NFC antenna for banking applications would “fundamentally diminish” the level of security Apple aims to provide.

Apples letter also points out that one of the four banks in the bloc argues that Apples terms and conditions for Apple Pay are too restrictive, but the bank has yet to sign the confidentiality agreement Apple requires before it discloses the full details of the service, so the bank should not have the full information on Apple Pays intricacies.

“Unfortunately, and based on their limited understanding of the offering, the (banks) perceive Apple Pay as a competitive threat,” said Marj Demmer, an spokesperson for Apple Pay who wrote the letter. “These banks want to maintain complete control over their customers. The present application is only the latest tactic employed by these competing banks to blunt Apples entry into the Australia market.”

Apple went as far to call the banks teaming up a “cartel” that would be illegal under Australias competition laws. So far, over 3,000 banks worldwide have accepted Apple Pays conditions in order to integrate it into their offering.

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