Higher education minister Margaret Hodge has admitted she is worried about the future funding of universities.
Speaking to students at the University of London Union, Ms Hodge also admitted that there was a risk the government could reach its 50 per cent participation target by 2010 without increasing the proportion of poorer people in higher education.
On funding, the minister said: "Investment in institutions worries me an awful lot because of underfunding over the generations."
A spokesman for the Department for Education and Skills said Ms Hodge was battling for more cash for university teaching and research. He said she was hopeful that the outcome of the spending review this summer would provide additional money.
Universities must wait for the outcome of the spending review, due in July, to see if the government's plans for the sector are backed with more money between 2003-04 and 2005-06.
Reaffirming the government's commitment to widening participation, Ms Hodge said: "We could get there without changing in any way the sort of people that go to university. If we do that, I will feel we will have failed."
The Liberal Democrats pointed out that a year ago the then higher education minister Baroness Blackstone said that the participation rate for 18 to 30-year-olds was 44 per cent. The education department has confirmed that it is just over 41 per cent.
Lib Dem higher education spokesman David Rendel said: "The government's task is going to be half as hard again as they expected - and their claims were hardly credible to begin with."