Cambridge University has denied it is to charge top-up fees for its students.

The vice chancellor Sir Alec Broers has publicly intervened to stop rumours that Cambridge - along with the country's other top universities - are secretly preparing detailed plans to charge undergraduates extra.

His denial comes as the city's Students Union urged members not to donate cash to the university as a way of marking their protest at what they called the privatisation of the sector.

Sir Alec said Cambridge had made no decision to introduce top up fees and would "prefer not to go down that route".

Sir Alec Broers aims to stop rumours

However, the Government has included top-up fees in a consultation document on the future of higher education due to be published next month.

Earlier this year a confidential paper discussed by London's Imperial College's ruling council said "it seems likely" the government would propose removing the limitation on fees.

The paper said the results of the government's "transparency review" of higher education had shown it cost about �10,500 a year to teach a student in laboratory-based subjects.

'Loan debt'

Imperial College's current funding from the Higher Education Funding Council for England teaching grant and from fees is about �7,700 per student.

"Hence the college loses around �2.8K p.a. for each student that it teaches," the paper said.

The Department for Education said: "We accept that students will leave university with debt.

"But the fact is that student loan debt will be repaid only when the students can afford to do so."