Headteachers dealing with protests over LGBT lessons should have been given more support, the government’s chief adviser on countering extremism has said.

Campaigners held banners saying “Don’t confuse our children” and “Let kids be kids” outside Parkfield community school in Birmingham after books featuring same-sex couples were used in a diversity programme.

The school decided to suspend the No Outsiders lessons in March until an agreement could be reached with parents.

But Sara Khan, who became a government adviser in January 2018, likened the protesters to a “mob”.

Speaking about the Department for Education’s response to the issue, she told BBC’s Panorama: “I think they were too slow to respond. There’s a lot of confusion about what’s actually being taught and I think [the] DfE could have played a very important role in clarifying to parents this is what’s actually being taught, not the misinformation that we’re seeing out there.

“It’s a mob chanting and shouting and engaging in intimidating and threatening behaviour. And I think we have to recognise that and call it out for what it is.”

No Outsiders teaches according to the Equality Act, and the school’s assistant headteacher Andrew Moffat said it could not pick and choose which elements of it to apply.

Pupils are taught about diversity, tolerance and acceptance in a broad curriculum encompassing LGBT rights, same-sex relationships, gender identity, race, religion and colour.

Last month, Moffat revealed the daily demonstrations outside the school gates had left some children in tears.

He said the lessons did not make reference to sexual acts and pupils were simply read stories involving people with different families to their own.

Damian Hinds, the education secretary, told the BBC: “We want children to grow up understanding that some people are different, some relationships are different from what they may have experienced, but all are valuable.

“We trust individual schools, individual headteachers, to know their cohorts of children and to determine how and when to address what can be obviously sensitive subjects.”