A doctor has been “sacked” as a medical assessor for a government department after refusing to renounce his Christian belief that gender is determined at birth, the Sunday Telegraph can reveal.

Dr David Mackereth has worked for 26 years as an NHS doctor but was told he could not be employed as a Department for Work and Pensions (DWP) disability assessor if he refused to identify patients as being of a sex that they did not see themselves as.

The 55-year-old father of four believes sex is genetic and biological, so established at birth.

He now claims his right to freedom of speech has been denied and he has been classed “unfit” to work for the department because of his religious convictions.

And, the medic from Dudley in the West Midlands fears many other professional people of faith could also be dismissed simply for holding opinions about gender that are “centuries old”.