The number of foreign students given visas is to be slashed as part of a crackdown on abuses of the system.
Home Secretary Alan Johnson is bringing in tougher rules, including demanding that applicants are 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 about 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.
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.
“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.”
The new rules will not require legislation and 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 20.
Those on courses lasting less than six months will not be allowed to bring dependants at all, while the dependants of students on below degree-level courses will not be allowed to work.
Student visas for below degree-level courses will also only be granted for institutions that are on a new register, the Highly Trusted Sponsors List.
Most if not all publicly funded universities and colleges are expected to be on the roll.
Shadow home secretary Chris Grayling said: “The student visa system has been the biggest hole in our border controls for a decade and ministers still seem to be floundering around trying desperately to correct their own mistakes. They should be ending the situation where a student visa is a way of coming to the UK to stay by banning the practice of moving from course to course in order to stay on and stopping overseas students from applying for work permits without going home first.
“And overseas students should pay a cash deposit which they lose if they don’t leave the country when their courses are over.”
Liberal Democrat home affairs spokesman Chris Huhne said: “The biggest hole in the student visa system is caused by the Tory and Labour abolition of exit checks, which means we do not know if someone has left once their visa runs out.
“We need to restore immediate control of our borders.”
Speaking on BBC1’s Andrew Marr Show, Mr Johnson rejected the idea of cash deposits.
“Many, if they are coming here for illegal migration, will pay thousands of pounds to usually criminal gangs,” he said. “The thought of losing a bond is not going to solve this problem.”
He also denied the system had been lax before.
“We closed down 200 bogus colleges,” Mr Johnson said. “By 2011, we will have the most sophisticated system in the world to check people not just coming into the country but to check they have left as well.”