Progress on LGBT issues is at risk of “slipping backwards” as campaigners force schools to suspend lessons about diversity, a former senior figure at the Department for Education and Ofsted has warned.

The message from Luke Tryl, special adviser to Nicky Morgan when she was education secretary, comes amid parental protests against lessons about LGBT rights and same-sex relationships.

This month, Parkfield Community School in Birmingham suspended its use of the No Outsiders programme, which teaches tolerance of diverse groups, following protests from parents and campaigners.

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And today, it was revealed that four more schools in the city have suspended the lessons.

Cabinet minister Andrea Leadsom caused controversy this morning when she said parents should be able to choose when their children are “exposed” to information about LGBT people.

LGBT education under threat

Speaking before today’s developments, Mr Tryl, who was previously head of education at Stonewall, told Tes: “I do genuinely think that, for the first time, we are at risk of seeing things slip backwards.

“I think there’s an assumption that the battle was won.

“We made huge progress, but I think the current climate in politics - ‘has the pendulum swung too far?’ - is now leading to some people feeling they can push back much more, and much more aggressively, so we are seeing it in Birmingham.”

Mr Tryl was Ofsted’s director of corporate strategy until he took over the New Schools Network free-schools charity this month.

He said: “I think social media is part of [the problem]. I think part of it is this populist backlash that we are seeing.

“It’s not just here. You’ve got Trump’s transgender troops ban.

“As I was leaving Stonewall, I thought maybe it’s time to say ‘job done’, or just to move into the international work, because clearly there’s stuff to be done there.

“But I look at it now and I think, ‘No, there are people who don’t want kids to know about LGBT issues. You have got the protests you saw. You have this really vicious anti-trans backlash, so there is still a lot more to do.’”

Mr Tryl described the role of schools and teachers as “vital”, and called for more support for headteachers who are trying to teach about diversity.

He added: “I think schools should be preparing young people for life in modern Britain, and they should be particularly exposing young people to ideas and concepts that they won’t find within the home - this idea that society is made up of different people.

“You need to teach tolerance early; you need to teach that difference is OK early.

“I’m very passionate about talking about things that bind us together as well, but I think inclusive relationship education should start in primary school and go through, and I think we need to do more to back heads when they are trying to do this stuff.”

He said it was right for faith institutions to also teach what their religion says, but added: “There is no excuse for keeping kids in ignorance.”