The decision to cancel a visit by a gay young adult author to a Catholic secondary school has left many pupils and members of staff "unnerved and upset", Ofsted said.
The schools watchdog carried out a snap inspection of The John Fisher School in Croydon on March 16 after the planned visit by Simon James Green to the boys’ secondary was axed following an intervention by Southwark Archdiocese.
Mr Green had been invited to the school for World Book Day to talk about his novel Noah Can’t Even, which features a gay character.
Southwark Archdiocese said in a statement that "from time to time, materials and events emerge for consideration that fall outside the scope of what is permissible in a Catholic school".
The Ofsted monitoring report said the decision had "unnerved and upset many in the school community".
It added: "Some leaders, staff and pupils have been left feeling angry, confused and frustrated. Others are worried about the impression these events might give of the school’s ethos."
It praised the leadership team, who had fully supported Mr Green’s visit, for "steering the school well through this difficult time".
It added that "immediate steps must be taken to restore stability to governance, and in turn ensure that leadership is provided with the support and challenge needed to build further on the school’s strong provision for pupils’ personal development".
The report, addressed to head Phillip McCullagh, said the school is a "caring" community, adding: "Pupils described the school as one where, ‘everyone just fits in’, irrespective of faith, background or sexuality.
"They said that leaders and staff make clear that ‘it is okay to just be you’. Pupils are rightly proud that this is the case.
"Leaders recently invited a well-known, published children’s author to visit the school to talk about his career and the publication process.
"This visit was a planned part of the curriculum offer. Some of the author’s books feature gay characters and their experiences."
The report said the archdiocese’s decision to impose an interim executive board after suspending the governing body – which voted to back the school leaders’ decision not to cancel the visit – was "made unilaterally and without due regard to the published statutory guidance regarding the appointment of IEBs".
As reported by the i newspaper, members of the National Education Union at the school are set to start a strike on Thursday to protest against the diocese’s actions.
Ofsted said a copy of the letter would be shared with the governing body and the director for education for the Archdiocese of Southwark.