CHILDREN should be allowed to decide what sex they are without judgment or derision from teachers, the Church of England has said.

Nursery and primary school pupils in particular must be free to discover the ‘possibilities of who they might be’, says the organisation’s first guidance on transphobic bullying.

‘A child may choose the tutu, the princess’s tiara and heels and/or the fireman’s helmet, tool belt and superhero cloak without expectation or comment,’ teachers at 4,700 schools have been advised.

But some critics warned that the guidance — with a foreword by the archbishop of Canterbury Justin Welby — would create a ‘climate of fear’.

‘Any expression of dissent in any way or a slip of the tongue you become labelled hateful, and that’s not Christian,’ said Andrea Williams, of the Christian Law Centre. ‘We’re all against bullying but, in framing the debate as they do, they are in danger of becoming the bullies.’

The archbishop tells teachers: ‘We must avoid, at all costs, diminishing the dignity of any individual to a stereotype or a problem.’ The guidance adds: ‘It may be best to avoid labels and assumptions which deem children’s behaviour irregular, abnormal or problematic just because it does not conform to gender stereotypes or today’s play preferences.’

The advice, which also tackles biphobic bullying, comes three years after the church first issued guidelines on homophobic bullying.

LGBT rights group Stonewall said Mr Welby should be congratulated for sending a ‘clear signal’.

But Christian groups said school staff already risked losing their jobs for ‘misgendering’ children.

Ms Williams said the ‘tragic’ church advice was buying into the Stonewall agenda which ‘isn’t tolerant at all’.

Maths teacher Joshua Sutcliffe, 27, faces disciplinary action for calling a transgender pupil at his Oxfordshire school a girl when she identifies as a boy. The part-time pastor said it was a slip of the tongue.