Net migration to Britain rose by more than 20 per cent last year amid a surge in the number of students coming to the country. Net long-term immigration was 196,000, compared with 163,000 in 2008, a rise of 33,000, the figures from the Office for National Statistics showed. The number of visas issued to students rose 35% to 362,015 in the year to June.

Increasing numbers of foreigners have been arriving in the country claiming they are attending colleges and universities since a points-based system was introduced by the Labour Government. Campaign groups have claimed the system is a loophole, and pointed out that many British students are giving up their plans to pursue further education because of unprecedented places.

Damian Green, the immigration minister, has announced that there will be a thorough review of the rules.

Many students enter Britain to take legitimate degrees, with universities increasingly seeing them as a lucrative source of income at a time of cuts to higher education budgets. Recent research showed that as many as a third of universities were preparing to increase the number of foreign undergraduates they admit from September.

As well as attending traditional universities, tens of thousands of foreign students have been admitted to 600 “lower tier” colleges, at which it is easier to gain a place but which are still accredited to hand out bachelor degrees.

Last year, it emerged that some of these colleges offered qualifications in subjects such as circus skills, acupuncture and ancient medicine. Many of their students are given the right to work in Britain after graduating. About 4,000 illegal immigrants are also thought to have taken advantage of bogus colleges to slip into the country.

Other figures released by the Home Office today showed the number of asylum seekers arriving in Britain fell sharply in the second quarter of 2010.

The Home Office said there were 4,365 applications for asylum between April and June – a 29% fall on the 6,110 applications in same period last year. Two-thirds of this decrease was due to a drop in applications from Zimbabwe, down to 405 from 1,560 in the same period last year.

There was a 15% fall to 2,380 in the number of asylum seekers leaving and a 13% fall to 11,750 in the number of people departing in non-asylum cases.