If you come from anywhere else in the world outside of the EU or EEA you need to produce one of:
A passport or other travel document endorsed to show that the holder can stay indefinitely in the United Kingdom, or has no time limit on their stay.
A passport or other travel document endorsed to show that the holder can stay in the United Kingdom; and that this endorsement allows the holder to do the type of work you are offering if they do not have a work permit
An Application Registration Card issued by the Home Office to an asylum seeker stating that the holder is permitted to take employment.