The number of foreign students given visas is to be slashed as part of a crackdown on abuses of the system, it has been revealed.
Home Secretary Alan Johnson is bringing in tougher rules, including demanding that applicants be able to speak passable English and banning those enrolling for short courses from bringing dependants.
Tens of thousands fewer visas are expected to be granted as a result of the measures - although the Home Office refused to give any estimate.
The "points-based" system was introduced around a year ago, requiring students to secure 40 points to come to the UK. Applicants are given 30 for holding a course offer from a college or university, and 10 for proving they can pay the fees and support themselves while in the country.
However, there has been criticism that the arrangements have allowed terrorist suspects and other would-be immigrants to gain entry into Britain, and simply stay on despite their visas being temporary.
Mr Johnson said: "We created our points-based system so that we could respond quickly to changing circumstances when necessary to raise the bar students have to meet to come to the UK.
"We remain open to those foreign students who want to come to the UK for legitimate study - they remain welcome. But those who are not seriously interested in coming here to study but come primarily to work - they should be in no doubt that we will come down hard on those that flout the rules. I make no apologies for strengthening an already robust system."
The new rules will not require legislation, and are due to come into force imminently.
Would-be students from outside the EU will have to speak English to a level just below GCSE standard (treating English as a foreign language), rather than beginner level as at present.
In a bid to protect jobs for British youngsters, students taking "below degree level" courses will only be permitted to work for 10 hours a week, instead of the current 20.