A top selling British children's author, who is also a minister of religion, has been thrown out of school for "swearing" in a talk to 12 and 13-year-olds.

Reverend Graham Taylor, who wrote the novel Shadowmancer, which centres on witchcraft and battling evil, said teachers became upset because he used the words "crap, poo, fart and bogey" in his talk at Penair School, in Truro in south-west England.

"I think that my language was appropriate," he said.

"Language changes and words that once were deemed unacceptable are now part of our culture."

The school said in a statement that teachers had asked Rev Taylor to leave after the children became excitable on hearing his "inappropriate" language.Shadowmancertopped British book charts for 15 weeks and the film rights have been sold for $4 million.