A school has been accused of "bullying" its pupils into colouring in their shoes with black marker in order to meet uniform regulations.

Harris Academy in South Norwood, London, allegedly put 12-year-old student Ayla Roberts in a referral room because she had pink stitching on her otherwise completely black shoes, Your Local Guardian reported.

Ayla's mother, Sophie, called the measures "completely over the top".

Sophie told the local paper she used mascara to hide the stitching while Sophie's other son, Lamel, was "forced" to use black permanent marker to cover white lining at the top of his school shoes.

"It is ridiculous. I was in hospital at the time and found out they had bullied him into ruining his own shoes," she added. "It is vandalism. They are not cheap shoes."

The academy, which was rated outstanding in 2010 by Ofsted, has around 1,100 pupils on its school roll.

The school said it would not comment on individual circumstances but a spokesperson said:

"It is important to the Academy, and to other students and staff, that everyone looks smart and wears their uniform correctly.

"It is important to be consistent in how school rules are applied and parents and carers are very supportive of this."

In 2011, charity Family Action warned more academies and free schools were putting parents under pressure by demanding costly school uniform items.

The increasing cost of branded uniform, coupled with local authorities cutting clothing grants, was "breaking the bank for poorer families".