by political editor Paul Francis

The number of foreign students coming into the UK needs to be curbed and cannot be sustained, the immigration minister and Ashford MP Damian Green has said.

Mr Green said the government planned to tackle the issue after figures indicating that one fifth of students admitted to colleges were still in the UK five years after being granted visas.

Home Office data tracking non-EU migrants coming into the country in 2004 found that the largest group were students.

Of the 185,000 granted visas, 21 per cent were still here after completing their studies.

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Mr Green said he was concerned the figures suggested that academic studies were being used as a way for immigrants to settle permanently in the country.

Audio: Damian Green warns of too many foreign students

"Half of those who come here are not doing university courses, so they are not what most people would think of as students.

"I want to look much harder at those who are using the student route to come here to make sure that everybody who does come here is doing a legitimate and beneficial course at a proper institution."

He added that the problems were not primarily caused by universities but other colleges.

"We need to make sure there are no bogus colleges but we also need to make sure that the right courses are being offered to benefit students.

"We also need to crack down on dodgy agents who are using the student route to get people here.

"We need to end up with a system that is not necessarily tougher but one that is smarter than the one we have."