Taxpayers should fund bright children from poor backgrounds to attend private school, an education charity has declared.

Sir Peter Lampl, chairman of the Sutton Trust, has called for all places at leading fee-paying day schools to be awarded based on merit, rather than ability to pay.

Outlining the "open access" scheme in an article in The Times on Sunday, Lampl said Britain now has an "elite education system that benefits the richest rather than the brightest."

Parents would pay fees on a sliding-scale, depending on their means, he said.

Research conducted by the Trust reveals that over two thirds of England's top independent day schools (130 out of 188) were principally state funded up to 1976.

Social mobility has declined in Britain since the 1950s, after direct grant and local schemes were stopped in 1976, he said.

"Most of the independent day schools that were state funded still exist but now entry is for the most part dependent on ability to pay," Lampl wrote.

"We believe that the best way to change this is to introduce a scheme where all places at leading private day schools are awarded on merit alone - democratising entry so it's based solely on merit not money, thus opening up the schools to children from all backgrounds."

He said a trial conducted by the Sutton Trust with the Girls' Day School Trust at Belvedere School in Liverpool over seven years had seen the school become more diverse.

Around 30% of pupils had free places, 40% on partial fees and 30% on full fees.

As parents were sharing the fees, the cost per place to sponsors was less than the cost to government of funding a state school place, he said.

Lampl also suggested that several prestigious schools including Manchester Grammar, City of London for Boys and King Edward's Birmingham are interested in the scheme.