More than two-thirds of UK students would be put off university by tuition fees of £7,000 a year, a report says.
The National Union of Students/HSBC survey of 3,863 current students found almost half would have been put off university if annual fees were £5,000.
It comes as the Times reported claims the forthcoming Browne Review of student finance is set to recommend raising fees to £7,000.
The Browne Review will not comment on this report.
The Times also claimed the review team had not been persuaded by arguments for a graduate tax, whereby students pay back the cost of their university education through the tax system.
It added that the Browne Review, due to report in October, recognised that vice-chancellors would need to be able raise their fees to at least £6,000 or £7,000 to engender competition between universities.
NUS president Aaron Porter said student finances were already at breaking point
He added: "This is clear evidence of the need to do away with the damaging and unpopular fees system, if we are not to shut out many thousands of young people from going to university, particularly those from poorer backgrounds.
"The financial pressure on young people is mounting, and an increase in fees to £7,000 would, according to universities' own figures, consign a generation to unsustainable mortgage-style debts in excess of £32,000."
General secretary of the UCU lecturers' union Sally Hunt said: "Lord Browne needs a reality check before he delivers his funding review if a fee hike is on the cards.
"He needs to look again at the idea of taxing big business for the substantial benefit it gains from a plentiful supply of graduates, rather than merely looking to penalise students further.
"Increasing fees or other financial barriers to higher education is not the way to deliver a world-class university system. The uncomfortable truth is that for the vast majority of people in this country higher fees would be a disaster."
The NUS/HSBC survey reflects research published in the summer by the Sutton Trust that suggested most would-be students would be put off studying at university by a fee-hike to £7,000.
Six out of 10 students felt they should not have to pay fees, and those who did thought they should only pay about a fifth of their tuition costs, the survey said.
And of those who believed that they should pay fees, they thought they should pay about a fifth of their tuition costs - about £1,680 a year compared to the current £3,225.
The survey also found 60% of students said they could not have afforded university without support from family and friends.
Parents from wealthier backgrounds are paying more than half of students' living costs compared to about 15% for poorer parents.