The cost of going to university could double under the coalition government's plans to introduce a graduate 'contribution', a union has warned.
It follows higher education minister David Willetts' tacit acceptance of business secretary Vince Cable's calls for a graduate tax yesterday.
The Liberal Democrat approach had appeared at odds with that of the Conservatives. But the Tories appeared to back down yesterday when Mr Willetts told The Andrew Marr Show: "We do have a preference for a way of going forward that involves graduates after they have got into work."
This "contribution", as he put it, could see the cost of a university degree rise significantly, the University and College Union (UCU) warned.
Under the current system, those earning the national average full-time salary take 6.7 years to pay back £10,182.
A three per cent graduate tax on all earnings for 20 years would cost £19,150, the UCU claims. A five per cent graduate tax on all earnings over £15,000 for the same period would cost £23,682 - while a lifetime seven per cent tax on graduate earnings over £15,000 would cost £50,917.
"Parents and students will judge proposed changes to student finance on whether they make university more expensive or not," UCU general secretary Sally Hunt said.
"Whatever scheme is proposed to replace fees, the government must ensure that studying for key professions remains attractive and that the prospect of prohibitive costs over a lifetime will not put off the next generation of innovators and public servants."
Lord Browne's review of higher education funding is expected to report in the autumn. The Lib Dems are permitted to abstain on the issue in the Commons under the terms of the coalition agreement.