A foundation year run by elite universities to help students from non-traditional backgrounds to win places is being promoted by the Higher Education Funding Council for England.
But the institutions say that such a scheme could prove impractical as lecturers at top universities would not want to swap research for foundation-level teaching.
Hefce this week invited elite institutions to bid for extra student places for foundation courses. It states in a document: "We would particularly welcome bids for foundation years, or shorter courses, from institutions where entry requirements to programmes are particularly demanding. These should widen participation by assisting students from non-traditional backgrounds to gain the necessary knowledge and skills to enter such competitive programmes."
Unlike those on conventional access courses, these students would be eligible for financial support, including loans.
Rodney Eastwood, director of planning and information at Imperial College, London, said: "Anything that helps students from poor backgrounds to take advantage of our courses is welcome. But this is running a school - school science has been in decline for years and now universities are asked to teach it."
At University College London, the proposals were welcomed in principle but not in practice. Vice-provost Michael Worton said: "In terms of student numbers, we have reached saturation point."
A spokesman for the University of Warwick said that it would not reject the proposals out of hand. The university already buses sixth-formers to its maths department for extra tuition.
But Trevor Hawkes, who handles admissions for Warwick's maths department, said: "Academics have priorities: research first, teaching second and administration third. That doesn't mean to say that we neglect teaching but it's research that inspires it. Asking people to give up research time to teach a foundation course would be a challenge."