• Home Office advisers warn numbers may drop by 50%
• Big reductions also in cases of family reunions

The number of overseas students from outside Europe will have to be cut by more than half if the coalition is to meet its target of reducing annual net migration to Britain, the government’s own experts have warned today.

The home secretary’s migration advisory committee (MAC) says that overseas students and family reunion cases will have to bear 80% of the reduction if the coalition target of reducing net migration from 196,000 last year to “tens of thousands” a year.

Professor David Metcalf, the MAC chairman, said this could mean cutting the current annual flow of 163,000 overseas students from outside Europe by 87,000 with deep cuts also required in the 55,000 people who come to join their families settled in the UK.

This is the first time that an authoritative source has put a ballpark figure on the scale of the reduction in overseas students needed by the coalition to drastically reduce the flow of migrants into Britain. The details of the proposed cap on immigration are due to go to cabinet next week with an announcement shortly afterwards.

The migration advisory committee also warned the government that simply cutting the numbers of skilled migrants would only go about 20% of the way in meeting their target of reducing net migration.

The migration experts say ministers should also now look at cutting the 52,500 young adults who come to Britain each year on working holidays — many of them South Africans and New Zealanders working in pubs and bars.

“It is not possible to reduce net migration to tens of thousands by limiting work-related immigration alone. The committee assumes that work-related migration takes 20% of the total cut – its fair share – which implies that family and student migration must take the other 80%,” said Metcalf.

The MAC recommends today that the number of skilled migrant workers coming into Britain through tiers one and two of the points-based system should be cut by between 13% and 25% next year – limiting them to between 37,400 and 43,700 – when the permanent immigration cap comes into effect next April.

This would be even tighter than the current temporary cap, which has been in place since June. The MAC acknowledges squeezing the flow of skilled migrant workers in this way could damage GDP to the tune of £360m a year because of the positive contribution they make to the economy.

But Metcalf also made clear that while David Cameron has already exempted the 22,000 extra specialists and managers a year who came through intra-company transfers, their numbers would have to be strictly controlled instead by raising minimum salary level or qualifications to produce same effect: “There is more than one way to skin a cat,” said Metcalf, who added that 2,500 skilled migrants were coming into Britain each month via this route.

He also gave broad hint that he expected a new category of “specially talented people” to be created in tier one – which covers the most highly skilled – to ensure that the “brightest and best” amongst the scientific and other academic research communities were not excluded as a result of the immigration cap.

The MAC report, published today however, makes clear that if the government is serious about reducing net migration from 196,000 last year to 50,000 a year then restricting work routes into Britain could only do about 20% of the job.

Metcalf said that work-related migration has halved since 2004 while those coming to study had grown substantially. He said that the government’s goal implied a 146,000 reduction in annual net migration within the next four years, and overseas students would have to bear 60% of the cut while family reunion cases, currently running at 55,000 would have to take the remaining 20%.

Sarah Mulley, Associate Director at the Institute of Public Policy Research, said: “The migration advisory committee’s analysis shows clearly how difficult it will be for the government to fulfil its promise to cut immigration substantially. The government now faces an unpalatable choice between introducing a policy which it knows will be damaging to the economy and public services, or failing to fulfil a key promise to the electorate.”

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