Foreign students could face being sent back to their home countries after their courses finish under hardline plans reportedly being considered by Home Secretary Theresa May.
The move would mean non-European Union students would have to return home in order to apply for a work visa if they wanted to continue to live in the UK after they graduated.
The Sunday Times reported (£) that Mrs May wants a future Conservative government to "move towards zero net student migration" by sending home those who come to Britain on student visas.
The revelation is the latest move to cut net immigration - after the Tories resoundingly failed to meet their pledge to reduce it to "tens of thousands".
The newspaper quoted source close to the Home Secretary, who said: "Making sure immigrants leave Britain at the end of their visa is as important a part of running a fair and efficient immigration system as controlling who comes here in the first place.
"Theresa is pressing for the next Conservative manifesto to contain a policy that will make sure that anybody coming here on a student visa will have to leave the country in order to apply for a new visa of any kind.
"She wants to make the colleges and universities that sponsor foreign students responsible for ensuring their departure.
"And she wants to be able to fine colleges and universities with low departure rates and deprive the worst of them of their right to sponsor foreign students."
Under current rules most students switch easily to a work visa from within the UK rather than have to leave the country and then come back.
Mrs May has repeatedly clashed with Liberal Democrat Business Secretary Vince Cable - whose department has responsibility for universities - about foreign students.
Mr Cable has warned about tough rhetoric on immigration putting off students from countries including India from attending UK institutions and the Liberal Democrats would be highly unlikely to support any further tightening of the rules.
A senior Lib Dem source told The Sunday Times her plan made "zero economic sense" and could deprive the UK of highly-skilled graduates.
"Such a blunt instrument would not get our support," the source said. "The idea that you have people from abroad studying in this country and they become engineers or scientists of huge practical value to the economy and rather than have them stay here you immediately turf them out makes zero economic sense."
Mrs May's plan emerged after David Cameron insisted that only the Tories can offer "competence" on dealing with immigration, as part of the escalating immigration rhetoric arms race between Labour and the Tories.
Writing in the Daily Express, he said his government had addressed some of the problems inherited from a Labour administration that "let immigration get out of control".
He said: "I came into office with a single-minded determination to turn all this around - and real progress has been made.
"We put a cap on those coming here to work from outside the European Union - and we have seen the numbers fall significantly, close to levels last seen in the 1990s. Major work has been done to clamp down on the bogus 'colleges' that were really just a front for people to come here, with more than 800 of them shut down so far.
"On illegal immigration, we are making it harder for people who have no right to be here to live in the UK, by revoking their driving licences, stopping them from opening bank accounts and making sure landlords check their legal status.
"Crucially, once they have been identified, we have made it much easier to deport them."