Middle -class pupils are more likely to be rejected from Oxbridge this year because of a drive towards low-income students, the former head of Harrow has said.
Barnaby Lenon claimed some colleges may also want to recruit more international students, who pay higher fees.
It means affluent pupils picking up their A-level results tomorrow are unlikely to be able to keep their university places if they drop a grade.
Mr Lenon, who was head of Harrow for 12 years and is now Dean of Education at the University of Buckingham, said the squeeze will affect pupils at top state schools as well as private ones.
Every year, Oxford offers around 3,300 places and Cambridge has 3,650.