Education Secretary Michael Gove has thrown his weight behind plans for a new free school in North Croydon.
The Conservative MP backed proposals for a secondary school shaped jointly by parents and charity the Harris Federation, which already runs three academies, and sponsors three other schools in the borough.
During a visit to Harris Academy South Norwood on Tuesday he dismissed fears that further expansion of the Harris brand, which is affiliated with 29 London schools in total, could deprive Croydon families of choice.
Mr Gove said: "The Harris academies are undoubtedly the biggest force for social progress and social mobility in the whole of the south of London.
"For those people who think the Harris ethos isn’t for them, of course there are other schools which they can send their children to and it’s in the nature of Croydon that you have lots of schools close at hand. There is enough choice locally for people who are not keen on sending their children to a Harris school.
"But the Harris chain of academies has been hugely popular because it has provided parents with what they want."
The Harris Federation currently runs academies in Crystal Palace, Purley and South Norwood.
It has also sponsored Archbishop Tenison's High School, Cypress Junior School and All Saints Junior School, but has no direct relationship with these schools.
The Education Secretary also argued academies could help to offset the impact of cuts to supplementary education on ethnic minority children.
Croydon councillors last month voted against a review of its decision to cut funding for several black and minority education organisations.
Mr Gove said: "Ethnic minority children have had a raw deal because it has often been the case that they have suffered from a culture of low expectation.
"What you have in the best schools are opportunities for black and ethnic minority children to succeed academically and that is supported by a rich mix of supplementary and extracurricular activities as well."
He also said that Croydon authorities "can't afford to rule anything out" as they look to address a shortfall in primary school places.
He said: "We’ve got to do everything we can and that means working with local authorities like Croydon to identify sites where new schools might be built and to ensure that existing capacity can be better utilised so that existing schools can either develop larger classes or consider expansion."
There were 274 more applications than available primary places during the last application period.