Speaking on BBC Radio 2 yesterday, Charles Clark, education secretary, said that rather than paying up front, students would pay through the tax system later in life.

But the exact details have yet to be thrashed out. A government spokesperson said later that the tax may not apply to tuition fees but to top-up fees only. Detail over the amount that students will have to pay back are also under discussion.

'What you pay will depend on what you earn, so that if you're doing a very low-paid job you won't have to pay a very substantial amount,' said Clarke. 'But if you get a lot more in pay ... you will pay much more.'

The government is set to unveil its funding plans for higher education later this month.