Apple has made steps to discourage customers from installing unlocking software on their iPhone.

In an official statement, the company said that customers who have made "unauthorized modifications to the software on their iPhone violate their iPhone software license agreement and void their warranty".

Apple also said that "The permanent inability to use an iPhone due to installing unlocking software is not covered under the iPhone's warranty".

Attempting to strike fear into users who've installed the software, the company says that "it has discovered that many of the unauthorized iPhone unlocking programs available on the Internet cause irreparable damage to the iPhone's software".

It even goes one step further by suggesting modified iPhones could become "permanently inoperable when a future Apple-supplied iPhone software update is installed".

Apple plans to release the next iPhone software update, containing many new features including the iTunes Wi-Fi Music Store, later this week.