Ms Prague already has �10,000 worth of debt

The 19-year-old medical student gave the prime minister a grilling on top-up fees during a BBC Two Newsnight debate.

She told BBC News Online she spoke out so the other side of the argument could be heard.

"I don't accept that it is acceptable to get into �40,000 of debt," she said.

Burden of debt

"I face the prospect of being 25 without a mortgage and a �40,000 debt," Ms Prague pointed out, adding: "I am going to provide a social service. It's only fair that the government should contribute to the cost of my degree."

She has completed two years of her six-year course at Guy's King's and St Thomas' School of Medicine and already she is �10,000 in debt.

"When I applied to do medicine I didn't think about the cost," said the teenager, from north London, who already pays �1,000 a year in fees.

She believes it is fair students contribute towards their education - but she was particularly infuriated by the suggestion of Margaret Hodge when she was a higher education minister that it was wrong that "a dustman fund a doctor".

On Newsnight Ms Prague replied: "When he has a heart attack he'll be pleased that I went to university and graduated as a doctor."

The teenager who attended a comprehensive was the first in her family to go to university.

'Horrible situation'

She is unimpressed by Mr Blair's insistence that it was only fair for graduates, not taxpayers, to plug the gap in university finances.

The prime minister may believe he will win the crucial vote on plans for student top-up fees later this month but he has not won the argument as far as Ms Prague is concerned.

She was unclear about how exactly she would suggest the government fund higher education.

"I am not the prime minister and don't know much about how the budget works but it seems to me the rebel MPs have come up with alternatives," she said.

Ms Prague told BBC News Online she was in a fortunate position as her parents would do everything to support her financially to help her complete her course.

But she thinks others may not be so fortunate and may be put off going to university by the fear of being burdened with debt.

"It's a horrible situation. It saddens me that they may have wanted to be a doctor since they were a child and have fulfilled the criteria to get a place and not be able to do so," she said.

Ms Prague was nervous about confronting the prime minister as he faced students, parents, business people and academics in the latest of Labour's Big Conversations. But she said she had to speak out.

"How would he feel being saddled with a �40,000 debt?" she asked.