Under the proposal, those qualifying for free school meals would get third priority.

About 25% of pupils in Brighton and Hove receive fee meals, but this figure is expected to reach 28% by 2025.

The percentage of children on free meals in schools around the city varies from 15% at King’s School in Hove to 46% at Brighton Aldridge Community Academy in Falmer.

Carrie Goldsmith, also from Class Divide, said those schools with a high concentration of children on free meals “have to do an awful lot to make sure their pupils are in a position where they’re able to engage fully in the school day and learn”.

She said this placed additional pressure on schools.

“Our schools are rising to the pressure but if you’ve got a good school, it’s good because you can teach all children,” Dr Goldsmith added.