Use Arabic numbers / script as passcode

Hi,

How can I set my iPhone and iPad to use Arabic numbers or Arabic script for the passcode lock?

I can set the phone default language and and primary keyboard to Arabic, however it still makes me use British text and numbers for the passcode to unlock the devices.

What I was hoping to be able to do was use Arabic number so ١٢٣٤٥٦٧٨٩٩, instead of 1234567890 on the unlock screen.

Thanks