Boris Johnson, the new Shadow Minister for Higher Education, opened fire on the Government this week, warning that UK taxpayers could foot the top-up fee bill for tens of thousands of European students.
When top-up fees are brought in this September, admission to British universities will be free at the point of entry for all UK and EU students.
Students will be required to pay for their education after graduation once their salary reaches £15,000.
But Mr Johnson told The Times Higher that he believed that the Government had given no real thought to how it would collect payments when European students returned to their homelands after graduation.
He said: "One has a nightmare picture of British civil servants being dispatched to companies all over Europe to track down absconding students."
Mr Johnson argued that students from some Eastern European countries might, in fact, never reach the £15,000 annual salary mark at which they would be required to start repaying fees to their former universities in Britain.
He said that the British Government might struggle even to establish what graduates' income was or to compel them, in a foreign jurisdiction, to repay.
He added: "People like me instinctively want us to be the great educator of Europe. It is fantastic for British universities that we have this magnetic effect."
But Mr Johnson said: "It is something that needs to be addressed. The options may not be very attractive - do they introduce some sort of demented European Fee Repayment Agency? But it cannot be brushed under the carpet."
Bill Rammell, the Minister for Higher Education, said: "The Student Loans Company already has long experience of recovering loan repayments from UK graduates who move to other member states of the European Union. The company will use that experience in recovering loan repayments from EU nationals who return home after graduation."
A spokesperson for the SLC said that it was working on the issue.
Mr Johnson also used his first education questions session in the House of Commons last Thursday to ressurect the debate about supporting knowledge for its own sake in universities.
Charles Clarke caused outrage when, as Education Secretary, he told a conference in 2003: "The medieval concept of a community of scholars seeking truth is not in itself a justification for the state to put money into that."
Mr Johnson called on Mr Rammell to disassociate the party from these remarks.
After the debate he added: "I was trying to set out my own view of what higher education is. But to be honest I wasn't quite sure what Bill was saying."