Even as its alumni includes the wealthy and famous from around the world, the Oxford University this year is looking to weed out "thick and rich" applicants and ensure that admissions are made on merit.

Oxford's head of admissions said yesterday that an important aim of interviewing candidates was to identify teenagers from wealthy backgrounds or leading independent schools who had been "polished" but were not very bright.

He said that his role was to weed out "thick and rich" applicants and to ensure that all undergraduate places were awarded solely on merit.

Mike Nicholson, the director of undergraduate admissions at the University of Oxford, made the comments at a conference on access to top universities hosted by the Sutton Trust, a charity.

Oxford and Cambridge are about to embark on their annual round of academic interviews.

"I really don't care whether candidates are poor and bright or rich and bright. I want the bright ones. If they are thick and rich, they are the ones I am hoping our process can exclude," Nicholson was quoted as saying by The Times.

Critics of the interview process say it confers advantages on pupils at independent schools, many of which have developed expertise in preparing Oxbridge applicants and offer mock interviews and practice for aptitude tests.

"What our tutors are trained to do in their preparation is spot the candidate who is polished, but who actually has very little substance behind that polish, but also to identify the candidate who is nervous and may not yet be showing their full potential," Nicholson said.

"Oxford received a record 17,480 applications this year and will make about 3,500 offers with a view to accepting some 3,200 undergraduates next year," Nicholson said.

He said more than half of the academics interviewing candidates were from overseas, whereas 30 years ago most would have been Oxford graduates who had navigated its admissions system.