The race relations watchdog has warned that Britain’s segregated schools are a "ticking time-bomb waiting to explode", as figures showed a rise in pupils from ethnic minorities.
The Commission for Racial Equality said the UK was in danger of becoming a mini America, with schools segregated along religious and ethnic lines.
And Government figures showed one in seven primary school children in England now does not speak English as their first language.
Nick Johnson, director of policy at the CRE, said parents must stop sending their children to schools where most pupils are from similar ethnic or religious backgrounds.
And he suggested that schools should be given extra money for taking a racially mixed group of pupils.
Schools across Britain are becoming "increasingly segregated in terms of race and religion", he said.
"This should be of key concern to each and every one of us.
"We’re in fear of turning into a mini America, with racially determined schools and areas in all of Britain’s towns and cities.
"Schools are where our children first learn how to get along with people from other cultures and backgrounds.
"Racially segregated schools prevent this from happening.
"If a Muslim child is educated in a school where the vast majority of other children are also Muslim, how can we expect him to work, live and interact with people from other cultures when he leaves school?
"This is a ticking time-bomb waiting to explode."
Mr Johnson said he was particularly worried about Tony Blair’s controversial group of privately-backed city academies and trust schools.
Some of these schools are using their extra freedoms to "cream off pupils from certain ethnic backgrounds or religions, thus reducing interaction and increasing racial tensions".
"If schools are judged solely on the academic results of pupils, it’s hardly surprising that they are selecting white, middle-class pupils, who have more opportunities and are more likely to succeed.
"This is creating a culture of education by ethnicity.
He went on: "Given the choice, most parents are choosing schools where the majority of pupils are from similar backgrounds.
"This simply has to change if we are to go any way towards reversing this predicament."