Security has been increased on The X Factor amid claims by militant Omar Bakri that the show is anti-Muslim.

The preacher voiced his opinions after learning that this year's contestants are recording a charity single called 'Hero' to help British soldiers injured in conflict, according to The Sun.

Bakri, who reportedly warned Sir Paul McCartney that the "sacrifice operatives will be waiting for him" should he play a concert in Israel, told Muslims not to wear Help For Heroes wristbands or to buy or sell the show's charity single.

The 50-year-old, exiled to Lebanon in 2005, claimed on a website that the show is drumming up hatred and warned of the "dangerous implications" should his words be ignored.

"Some people may find excuses for those people, ignorance and so on. If after three days, if they continue, you are barred from these people and their deeds. Even watching the show - those people are committing a form, a type, of muadaat (hatred). And that action is a form of kufr (non-belief)," he said.

A show source said the issue was being taken "very seriously" and that CID and anti-terrorism officers had been called in. "We are in the process of discussing extra security measures for Saturday night’s live show," the source added.