The school head involved in a row about a transsexual supply teacher has won the backing of his union.

The National Association of Head Teachers has called for better guidelines on the employment of transsexuals in schools after Natasha Thoday was asked to leave Telscombe Cliffs Primary School by head teacher Andrew Kearsey because of her gender change.

An NAHT South-East spokeswoman said: "Mr Kearsey demonstrated he was in no way prejudiced against Ms Thoday when he welcomed her to the school in the knowledge she was transsexual."

The spokeswoman said the supply agency involved had told the school Ms Thoday was a transsexual prior to her appointment.

She said: "We are appalled no guidance has yet been issued by the Local Education Authority on the subject of gender reassignment and how this impacts on equality laws.

"It is not enough to simply send out a reminder to schools about equal opportunities."

Mr Kearsey has been unable to comment on the settlement reached with Ms Thoday following advice from East Sussex County Council.

A council spokeswoman said: "We have supported the head teacher and governors throughout this dispute and in the matter of compensation for the breach of regulations that took place.

"The wider issues of employment regulations and gender reassignment are relatively new for all employers and we will take account of experience in this case in producing further guidance for schools."

Ms Thoday, 35, began tribunal proceedings against the county council under the Sex Discrimination Act but accepted an out-of-court settlement of £3,780 in September.

Last week, she took her fight to be fully recognised as a woman to Rosie Winterton, the minister with new responsibility for transsexuals.

Ms Thoday said: "The meeting went really well and Ms Winterton took everything I said on board.

"She said it would take a long time, as it would be a matter of liaising with different governmental departments before anything became concrete. But I felt the wheels were starting to turn."

Brighton transsexual Persia West, Brighton Pavilion MP David Lepper and three civil servants were also at the half-hour meeting, in which the implications of a change in the law were discussed.

Ms Thoday said: "My next step will be to write to thank Ms Winterton for meeting us and start asking more specific questions.

"Transsexuals have a right to life like anyone else. We should not have to live in fear."