Parents in England have far more choice over schools than anywhere else in the industrialised world, according to a research project published yesterday.

The survey showed that 52 per cent of 15-year-olds were in their school because it was "known to be better than others in the area".

This is more than twice the average for the 26 other countries in the survey and and researchers claim this is a key reason for laying the blame for 80 per cent of social segregation in England at the door of state rather than private schools.

The researchers from Southampton and Essex universities delivered a warning that excessive segregation "may threaten present-day social cohesion". and harm exam results.

The findings will be seized upon with alarm by rebel Labour MPs worried that the Prime Minister's school reforms will lead to more selection. More than 90 have signed up to a strategy that opposes his moves to give new independently run "trust" schools a greater say over admissions.

The authors, John Micklewright, Stephen Jenkins and Sylke Schnepf, argue: "England's segregation is not driven by the existence of private schools."

The survey also found that 28 per cent of schools used some form of selection in their admissions policies.