Apple said in a statement released Wednesday that, unlike its competitors, it no longer can access user devices without a password, something that was possible so far.

"Thus, it is not technically possible for us to respond to government orders to pull data from devices that work with the iOS 8 operating system," the company said.

The security improvement protects information which can be stored in devices or Apple users' accounts such as photographs, emails, contacts, calls, messages, handwritten notes or multimedia content.

The measure is in response to accusations that the company cooperated with other technology companies and the US National Security Agency when they asked Apple for user details.

Apple has modified its encryption system so as to prevent itself from accessing the devices and user accounts, and this gets applied automatically once the user has set the password.

In an effort to distance itself from the accusations of collaborating with the US government, Apple said Wednesday that it had provided federal authorities with data of "less than 0.00385 percent" of the device users.