Conservative parents should be willing to take their children out of schools if they are “too woke”, a prominent headteacher has said.

Katharine Birbalsingh, head of Michaela Community School in Wembley, used a speech at a conference in London to warn: “If we don’t get on top of the culture that these schools are propagating, we will lose our country.”

In a speech that culminated in “Britain’s strictest headteacher” delivering lines from the film Gladiator, Ms Birbalsingh bemoaned children “leading” schools, attacked private schools for being more “woke” than state providers, and claimed children at some schools are allowed to wear ears and tails because they “identify as cats”.

She also called on the audience at the National Conservatism conference to act if they felt their children’s schools did not reflect their “small c conservative values”.

She said: “As GK Chesterton said, the true soldier fights not because he hates what is in front of him, but because he loves what is behind him.

“Well I’m asking, how much do you love your country? How much do you love the values that you claim to defend?

“Do you love them enough to tweet under your own name? Do you love them enough to change your child’s school to one that’s less woke and ignore the impact on your social status? Do you love them enough to do more than simply chat to your friends who already agree with you at dinner parties?

“For heaven’s sake man, stand up and be counted. As Russell Crowe says in the film Gladiator – a clip I regularly play to my staff: ‘Hold the line, stay with me, what we do in life echoes in eternity.”

Ms Birbalsingh added that it was not enough for conservatives to turn to private schools to instil their values.

She said: “What you don’t get is that the private schools are just like the state schools in terms of culture. In fact, in many ways, they’re worse.

“If you don’t like the woke agenda, then you had better avoid private schools like the plague. As sure as night follows day, the more privileged the space, the more woke it is.”

Throughout her speech, Ms Birbalsingh argued that schools had a vital role to play in determining the UK’s culture, but said few people had been paying attention to them.

She said: “From where I’m standing, it doesn’t seem like anyone cares. I’ve been shouting for decades about the importance of schools in the fight for values and culture. Culture is everything.”

Ms Birbalsingh has long been an outspoken critic of the education system and in January stepped down as chairwoman of the Social Mobility Commission so she could continue to speak out.

In her speech on Monday, she claimed that supporting England in the World Cup had come to be seen as “bizarre, especially in areas with large numbers of ethnic minorities or immigrants”.

She also described Whitney Houston hit The Greatest Love Of All as “an inspirational song about never walking in anyone’s shadow and living what you believe, but it never mentions duty or sacrifice”, while arguing that too many schools had allowed children to determine the culture rather than adults.