A “sex-obsessed” Islington teacher who told a 16-year-old girl he would “have” her has been banned from all English classrooms for life.

Dr Michael Davis, who taught at all-girls school Highbury Fields, in Highbury, from 2007 to 2008, was found to have made a string of inappropriate comments to pupils aged 11 to 16.

The Teaching Agency, who made the decision on the life-long ban on July 2, heard how Dr Davis wanted to stalk his female pupils on Facebook to keep an eye on what they were up to.

Julia Hodson, deputy head at the Highbury school, told the panel that while no pupils had complained directly about Mr Davis, some teachers had reported concerns about inappropriate behaviour.

Dr Davis, head of sixth form and a history teacher, was warned twice about his behaviour before being suspended in June 2008 pending an investigation, but a compromise was reached and he left the school the following month.

Pupils from Year 8 and 10 were asked to write down anything unusual. One Year 8 student said: “In lessons Dr Davis keeps talking about sex and stuff and its not really relevant to the lesson.”

Another girl the same age said he used sexual words like “breast,” “rape” and “sex”. A third said: “In nearly every lesson Dr Davis always talks about sex. I think he is obsessed with that subject.”

The panel heard that he told students, aged 14 and 15, “the best form of exercise for people our age was sex”.

Dr Davis was also alleged to have said to a sixth form student “If I was younger and you were older, I’d have you.”

The panel found him guilty of unacceptable professional conduct and banned his from teaching in England indefinitely, although he can apply for the ban to be lifted after five years.

Alan Meyrick, decision maker for the panel, said: “It is evident that the behaviour of Dr Davis falls seriously below that expected.

“The repeated use of sexualised language and sexual references falls significantly short of the behaviour expected of a teacher.”

An spokesman for Islington Council said: “We expect the highest standards from all our teachers, and support the prompt action of governors in this case.

“We also support the Teaching Agency and the functions of its professional conduct panel.”

Dr Davis’s website says he is a member of the Royal Historical Society. He has had several historical novels and a biography on Prince Bishop Henry of Blois published and is an expert on the Bayeux tapestry.

Dr Davis said that on the advice of his solicitor, he was not commenting.