Imperial College London has become the first university outside Oxbridge to set tuition fees at £9,000.

Sir Keith O'Nions, rector of Imperial, confirmed last night that fees would be set at the £9,000 maximum for British and EU students starting in 2012.

The National Union of Students warned that the move will force "virtually all" universities in the capital to form a "cartel" and charge the maximum.

Deputy Prime Minister Nick Clegg has vowed to ensure that only a few universities charge the top rate.

The move has led to fears of a student "brain drain" with growing numbers of UK youngsters opting to study for their degrees full-time abroad.

Figures disclosed yesterday show that a record 22,000 UK youngsters have opted for full-time study overseas.

The percentage of UK students travelling overseas is higher (at 1.7 per cent) than China (1.4 per cent) and India (1 per cent) – the two fastest-developing nations traditionally associated with sending scores of students overseas.

The figures, based on research carried out by the Department for Business, Innovation and Skills, were revealed at a conference on the future of higher education in London yesterday.

The rise comes after a number of overseas universities – most notably Maastricht – have launched recruitment programmes in the UK, pointing out that their courses are already cheaper than studying in the UK.

Vincenzo Raimo, director of Nottingham University's international office, predicted the numbers studying overseas would continue to rise. "The total cost of a three-year programme of study [once the new fees of up to £9,000 a year come in] will be – give or take a bit – £45,000."