Will Knowland, an English teacher at Eton, who was sacked for allegations of gross misconduct, has had his appeal rejected, the school’s headmaster, Simon Henderson, said on Monday.

Henderson told parents that it was “frustrating” that the debacle had played out so publicly but called on them and Eton Masters to “move forward together for the benefit of the boys.”

The headmaster of the elite 580-year-old all-boys school said that intellectual freedom “lies at the heart” of an Eton education but claimed that there are “limits to the freedoms that teachers have.”

"It has been suggested by some that intellectual freedom is somehow being compromised within Eton. It is not."

The £42,500-a-year college has contended that the dismissal was a matter of “internal discipline” and “not a matter of free speech.”

Henderson said the school needed a period of evaluation and to “consider how we continue to maintain a positive dialogue between those who hold opposing views.”

Knowland was sacked earlier this year after he posted a lecture online when he had been told he could not deliver it to the pupils. It was decided that the lecture was in violation of the school’s commitments and did not provided the students with a balanced viewpoint.

A number of points were highlighted as toxic, including a claim that male rape was more prolific than male-on-female rape, along with comments on other sexual assault patterns without figures to back this up.

Other parts of the lecture which encourages students to consider what it means to be masculine and question gender perception touches on courage, honour, chivalry, innate aggression and the notion of ‘manning-up’.

Knowland also cites a story from the Marie Claire magazine entitled ‘Why I Left My Beta Husband’ where the author discusses why she said “I felt like the man in our relationship.”

The school claim they were left with “no choice” but to ask Knowland to remove the video from YouTube as it fell foul of equality laws. Knowland refused and the video remains online.

Knowland has received the support of many of his pupils and has raised over £60,000 for potential legal fees.

The Free Speech Union (FSU), a mass membership public interest body which is supporting Knowland, says that they will lobby for an amendment to the Equality Act 2010, a law which says it is unlawful for any education provider, including a private or independent provider, to discriminate between pupils on grounds of protected characteristics and beliefs.

General Secretary of the FSU, Toby Young, said: “The Act was never intended to prohibit teachers from introducing their students to a broad range of different perspectives on controversial topics, such as sex and gender.”

The lecture, which promotes critical thinking albeit without considerable academic rigour, has been viewed over 130,000 times on Knowland’s YouTube channel.