School inspectors have heavily criticised a private faith school in Tooting for keeping boys and girls illegally segregated.
But Al Risalah School says it plans to formally separate into two schools - one for boys and the other for girls - rather than educate both genders together.
Ofsted inspected the school in March and in the report released this month (May) rated the school as 'requires improvement' because of the segregation, and said it is breaching the Equalities Act 2010 by keeping pupils separate.
The report reads: "The school’s work to promote pupils’ personal development and welfare requires improvement.
"The school’s otherwise effective work in this area is undermined by the unlawful segregation by sex.
"Pupils are not able to work or socialise with the opposite sex. Girls and boys arrive and depart at separate times, are taught in separate classes and do not share the same breaks.
In a recent letter to parents, Headteacher Suhayl Lee reassured them that preparations to split the school were going well and pointed to all the areas the school was praised for by Ofsted.
These included strong exam results, good behaviour and effective leadership.
But Alastair Lichten, head of education at the National Secular Society, said this was undermined by the school's policy of gender segregation.
Since a 2017 ruling that Birmingham school, Al-Hijrah, was unlawfully segregating its pupils, faith schools still keeping children separate have been under scrutiny, and many like Al Risalah are considering formally splitting.
Mr Lichten said: "Segregation has formed part of efforts to mould pupils into narrow religious-based gender roles."Such efforts clearly breach the independent school standards and deny children the right to make their own choices in life and should have no place in our education system.
"Simply splitting into two separate schools will not completely address these concerns."
Mr Lichten pointed to a "growing crisis" in the independent faith school sector. He said more than half of the last round of private schools issued with warnings were faith-based.
He added: "Whatever type of school they attend, children have the right to education that opens opportunities for them and prepares them for life in modern Britain rather than one that narrows their potential."
Photo credit: Google street view - Al Risalah School