British universities could lose out on millions of pounds annually if immigration policies are not changed, senior education figures have warned David Cameron.
In a letter to the Prime Minister, 68 chancellors, governors and university presidents warn that Government crackdowns on immigration could lead to foreign students going elsewhere, costing the British economy billions.
The letter echoes warnings from Professor Eric Thomas, president of Universities UK and vice-chancellor of the University of Bristol, earlier this month, when he warned that recent visa changes could deter foreign students.
Prof Thomas said he planned to write to the Prime Minister urging him to class international students as temporary rather than permanent migrants.
Those calls have been repeated in the letter to Mr Cameron, according to the Daily Telegraph. The letter says Britain attracts around one in 10 students who study outside their home country, generating around £8 billion a year in tuition fees.
Signatories include former Liberal Democrat leader Menzies Campbell, chancellor of St Andrews University, as well as broadcaster Lord Melvyn Bragg, chancellor of the University of Leeds.
They also include former Conservative minister Virginia Bottomley, chancellor of the University of Hull, and Patrick Stewart, chancellor of the University of Huddersfield.
Prof Thomas said previously: "The UK seems to be telling the world it doesn't welcome international students, while other countries are travelling in different directions.
"We are requesting that international university students should be removed from the net migration statistics for policy purposes, bringing us in line with our major competitors.
"We believe that this would help the Government by creating a clear differentiation between temporary and permanent migration, help universities whose international character is essential to their future success, and help the UK by contributing to economic growth."
International students contribute £5 billion a year to the UK economy, a figure that rises to £8 billion when EU students are included, with the potential to increase to £17 billion by 2025 and "create thousands of jobs", Prof Thomas has said.
If universities face a decrease in overseas admissions, they could each lose £5 million to £7 million a year, he added.
"There are significant economic benefits and growth in this area and we believe removing international students from net migration figures, which is what other countries are doing, will send very positive signals around the globe."
Recent changes include the fact that international students can no longer bring their dependants with them, unless they are taking a postgraduate course which is at least 12 months long, and there is a "more selective" system in place for students wanting to stay in the UK to work after completing their studies.
Immigration Minister Damian Green said: "There is no limit on the number of genuine students who can come to the UK and our reforms are not stopping them.
"But we are determined to prevent the abuse of student visas as part of our plans to get net migration down to the tens of thousands.
"When we announced our full raft of changes to the student visa route, Universities UK said that the proposals 'will allow British universities to remain at the forefront of international student recruitment'.
"Students coming to the UK for over a year are not visitors - numbers affect communities, public services and infrastructure."
Nicola Dandridge, chief executive of Universities UK, said: "We are keen to work with the UK Government to eliminate problems when they exist.
"The problem with the UK Government's proposals is to lump together genuine international students who come and then go with people about whom we may want to ask questions.
"What we are saying is take genuine international students, who come and then go, out of the definition of net migration equation and then we can really work with the Government on those who shouldn't be here."