The governor of a Birmingham school under investigation over allegations of an Islamic takeover plot has criticised Ofsted for asking how staff would handle a gay child.

The man, who wants to remain anonymous, told Sky News he believed inspectors had come to the school with preconceptions about the establishment.

He said: “The questioning was very inappropriate compared to a normal Ofsted. They asked us, on both occasions, ‘If a child is gay, what would you do?’ and questions like that were pushed to a long duration.”

Up to 18 schools are being looked at by the education watchdog amid allegations that hard-line Muslims are trying to seize control of schools in Birmingham.

It comes after an unsigned, undated letter was published claiming to outline “Operation Trojan Horse”, a blueprint to help conservative Muslims take control of schools.

The allegations, made public by The Daily Telegraph in a leaked report, include gender segregation in schools, discrimination against non-Muslim staff and pupils, and the introduction of Islamic ideologies into the curriculum.

Sheikh Shady al-Suleiman, an extremist preacher who “is known to extol… the stoning of homosexuals, anti-Semitic views [and is] sympathetic to al-Qaeda”, was invited to address students at Park View School.

At Golden Hillock School, any discussion of sexual orientation or intimacy was banned, affecting “the broad and balanced teaching of many subjects, including art and English literature”, the report warned.

Around 25 schools in Birmingham are also being investigated by the city council and the Department for Education.