More than 1,100 parents and churchgoers have signed a petition calling for the council to give one of two new secondary schools to the Catholic Church.
Father-of-two Anthony Kennedy visited most of Richmond’s Catholic primary schools to gather signatures and has written to the Archbishop of Westminster and the Archbishop of Southwark to ask for their support.
He called for the archbishops to “work constructively and imaginatively, both with each other and with Richmond Council, to secure this objective”.
The South West London Humanists group has campaigned against the council’s plans to build the borough’s first Catholic secondary school, saying they were about “exclusivity and privilege”. And Accord, which includes a coalition of Muslim, Hindu and Christian organisations, has also spoken out against the proposal.
But Mr Kennedy, of Clifford Avenue, East Sheen, said Catholic schools only discriminated against pupils based on their faith if they were oversubscribed.
He said: “My view is given there are a number of schools here anyway, and given there is a demand from those Catholic people in the borough who I understand make up about 20 per cent, then no great harm or disservice would be done by having a Catholic school here.
“We have got established Church of England schools and they are allowed to discriminate to the extent they can prefer Church of England pupils to anyone else.
“I suspect the reality is, and I can’t pretend otherwise, that a Catholic school would be likely to be oversubscribed because of the demand.”
The solicitor, who has a son aged nine and a five-year-old daughter at St Elizabeth’s Catholic Primary School, said Catholic parents were concerned about the quality of secondary education in Richmond and applied for places outside the borough.
He said: “They are very good schools, but involve relatively long journeys for relatively young children.”
Accord and the South West London Humanists group said both new schools, due by 2015, should be inclusive and should not segregate children based on their religion.