Giving children unfettered access to the internet “is like dumping them in Soho and saying, ‘have a wander’,” a porn film actor told students.

Johnny Anglais, a former teacher, told a debate in Cambridge that most “young people” watched porn.

He said he was not sure whether that was a “bad thing” and told a meeting of Cambridge University’s debating society that Britons had a “very immature” attitude to sex. Mr Anglais was speaking at the Cambridge Union Society last night as members debated the motion “This House believes pornography does a good public service”.

He said he first saw porn at 16 after finding his father’s “forbidden cupboard”.

“As a former teacher, I know the majority of young people watch porn – I don’t know whether it is necessarily a bad thing,” he said.

“(And) allowing a child free access to the internet is like dumping them in Soho and saying, ‘have a wander we’ll meet you back here in a few hours’.”