A maths teacher suspended for calling a transgender pupil a girl rather than a boy is suing his school for religious discrimination.

The Mail on Sunday revealed last month that Joshua Sutcliffe, 27, was facing a disciplinary hearing for accidentally 'misgendering' the student during a lesson.

The plight of the 27-year-old – who is also a pastor of an evangelical church – provoked widespread outrage.

He is now taking the school in Oxfordshire to an employment tribunal, claiming he has been victimised for his Christian beliefs - with his rights 'systematically and maliciously' breached.

The school head declined to comment, saying disciplinary matters were confidential.

Joshua Sutcliffe misgendered a student in an Oxfordshire school leading to his suspension

According to documents seen by The Mail on Sunday, he also faces claims that he is breaching equality policies by referring to the pupil by name rather than as 'he' or 'him'.

The teacher claimed he said to the teenager and a friend 'well done girls' when he spotted them working hard and apologised when corrected by the pupil.

Mr Sutcliffe said he was 'distraught' and had been reduced to tears as teaching was his life, and he branded the actions of the school as 'political correctness gone mad'.

The maths graduate, who gained his teaching qualifications at Exeter University, said he had no official instructions about how to address the student but along with other staff decided to use the pupil's chosen first name.

However, he has admitted that, as a Christian, he avoided using male pronouns such as 'he' and 'him'.

He believed this was consistent with the school's code of conduct and equality policies to show respect and tolerance, and he said he had encountered no problems with this.

He said he thought no more about the incident until the week before last when, after a parents' evening, he was unexpectedly called to the head's office to be told there had been a 'transgender complaint' against him and that he was suspended from teaching while it was investigated.

Mr Sutcliffe He was told to come to the school and sit in the staff room preparing work, but he was not allowed to discuss the situation with colleagues

He was told to come to the school and sit in the staff room preparing work, but he was not allowed to discuss the situation with colleagues.

He later discovered that the pupil's family had claimed he had not only 'misgendered' the pupil but had unfairly given the pupil a disproportionate number of detentions for poor behaviour, though this later claim was not upheld during the investigation.

It is understood that the family's main concern was that Mr Sutcliffe was picking on their child and they would not have complained about misgendering on its own as they are supporters of free speech.

Mr Sutcliffe said: 'I was absolutely shocked to be told by the head that I was under investigation. I didn't know what was happening. It was surreal, Kafkaesque.

'I said it was only one incident for which I had apologised, but he insisted the investigation would go ahead.

'I had always tried to respect the pupil and keep a professional attitude as well as my integrity, but it seemed to me that the school was trying to force me to adhere to its liberal, Leftish agenda.'

Mr Sutcliffe assumed the investigation would be brief and he would soon be back in the classroom, but he was questioned for an hour on the day after the meeting with the head and again last Monday, and was then sent a letter telling him to attend a formal disciplinary hearing this Wednesday, attended by the head and three governors.

He said: 'I have never been trained to deal with this sort of thing. I felt completely out of my depth and intimidated.'

In a statement released by the Christian Legal Centre today, the religious lobby group claimed Mr Sutcliffe had received no formal training on how to refer to the pupil, and referred to transgender as a 'delusion'.

He was due to take his former school and its headteacher to an employment tribunal on the ground of unfair dismissal.

The centre said: 'The child had self-declared as 'male', but Mr Sutcliffe, who had been given no formal instruction on how he was to refer to the pupil, said 'well done girls' in her presence.

'When the pupil became irate Mr Sutcliffe sought to diffuse the situation and apologised.

'Nonetheless, an investigation began during which time Mr Sutcliffe was prevented from teaching and forced to spend all his time in isolation in the staff room.

'Following the week-long investigation, the school found Mr Sutcliffe to have 'misgendered' the pupil, 'demonstrating discriminatory behaviours' and 'contravened the school's equality policy'.

'The school recommended dealing with the matter of 'misconduct' under its disciplinary policy.'

Documents seen by The Mail on Sunday show the investigation also heard uncorroborated claims that Mr Sutcliffe had made several other references to the pupil as a 'girl' and had inappropriately discussed religious issues in his maths lessons, which he denies.

He said he had raised religious issues such as the anniversary of the Reformation in his general tutor group, in which he encourages older pupils to discuss topical issues in the news, but not during maths classes.

Mr Sutcliffe, a pastor at an evangelical church in Oxford, also said that several years ago he had started a voluntary Bible club during lunchtimes at the school which had been well attended.

But this had been shut down earlier this year after he had answered a student's question on marriage by saying the Bible described it as being between a man and a woman, prompting a complaint about homophobia.

He said he had told senior staff carrying out the 'misgender' investigation that his private belief was that it was not wrong to call a person born a female a girl, but he would never do that publicly because he was a professional.

The investigation concluded that the 'misgendering' of the pupil and 'avoidance of using gendered pronouns contravenes the school's code of conduct with regard to demonstrating an awareness of sexual and cultural diversity of students and use of insensitive comments towards young people' and 'the use of religious comments in maths lessons demonstrates a failure to comply with school policies.'

The assistant head leading the investigation recommended that both were matters of misconduct that should be dealt with under the disciplinary policy.

Mr Sutcliffe said: 'I have been shocked and saddened by the actions of the school, which, in my opinion, reflect an increasing trend of Christians being marginalised in the public square, and unpopular beliefs silenced.

'While the suggestion that gender is fluid conflicts sharply with my Christian beliefs, I recognise my responsibility as a teacher and Christian to treat each of my pupils with respect.

'I have balanced these factors by using the pupil's chosen name, and although I did not intentionally refer to the pupil as a 'girl', I do not believe it is unreasonable to call someone a girl if they were born a girl.'

Andrea Williams, chief executive of the Christian Legal Centre which is supporting the teacher, added: 'This case is one of a flood of cases we are encountering where teachers are finding themselves silenced or punished if they refuse to fall in line with the current sexual and gender ideology being imposed on our children in schools.

'We all know how much we change during our teenage years. It is vital that during those years we help our children to live in the biological sex they were born rather than encouraging them to change 'gender'.

'If we encourage them to change gender it is not kind and compassionate; it is cruel.

'What we need is a culture in our schools which gives emotional support to children through puberty without encouraging them to make life-long decisions against their natural born biological sex.

'If we collude in the transgender delusion we do not serve our children well, we harm them.'

The former Conservative Party chairman Lord Tebbit said: 'It seems to me this is a mad world when someone is disciplined for stating a biological fact.'

The head said it would not be appropriate to comment on confidential staff disciplinary matters.

A letter written by Mr Sutcliffe to the school head teacher was also released, in which he said: 'As a Christian, I do not share your belief in the ideology of Transgenderism.

'I do not believe that young children should be encouraged to self-select a 'gender' which may be different from their biological sex; or that everyone at school should adjust their behaviour to accommodate such a 'transition'; or that people should be punished for lack of enthusiasm about it.

'Implementation of these ideas is detrimental to the welfare of children, which I believe should be a paramount consideration.

'However, as a professional, I was always careful not to breach my employer's policies so long as I was not forced to act contrary to my conscience.'

Mr. Sutcliffe claimed the school had 'systematically and maliciously' breached his rights, and has made it impossible for him to continue working for it.

He continued: 'I am more than willing to answer all the unjustified allegations you are now advancing against me, and detail my own grievances about your totalitarian 'equality' policies and practices.

'However, I intend to do so before an independent tribunal, not before yourselves acting as a judge and jury in your own case.

'I regret that our relations have reached this point, but I feel I have no choice but to bring legal proceedings against you without further notice.'