Britney Spears and Jason Trawick[Photo/Agencies]

Britney Spears has hired a spiritual advisor to assist her on 'The X Factor'.

The 30-year-old singer has joined the panel of the US version of the TV talent contest and has amused programme chief Simon Cowell with her demands, which include the religious mentor, 23 other support staff and a request for no "random" workers on the show be allowed to approach her.

A source told Closer magazine: "There are some rules, such as no random people approaching her - no runners or production staff, no one telling her she has to be somewhere at a certain time.

"She's also insisted on having around 24 of her own staff on hand, including a spiritual advisor, security, a doctor and psychologist.

"Britney's in regular touch with Simon and is asking for more and more. He's been laughing about it, saying she'd better pull it out of the bag after all this fuss. He's seen a lot during his years in the business but says she's another level."

Although Britney - who is engaged to Jason Trawick - is rumoured to be earning a seven-figure sum for the show, insiders claim she is only being paid per episode, to prevent any difficulties if she doesn't work out on the panel and has to be replaced in the way Cheryl Cole was last year.

The source added: "Insiders say the deal Simon has struck means he's only paying her episode, so if she's not performing, then she'll be replaced, just like Cheryl Cole was last year."

Britney is being joined on the panel by fellow judge Demi Lovato and returning mentors Simon and L.A. Reid.