Alarm bells went off among British conservatives recently, when new data for the year ending in June showed a large jump in immigration. Stemming the flow of foreigners has been a longtime priority for the Tories. Yet even they recognize that the UK is woefully short of fruit pickers, nurses and other kinds of labor. As a result, the spotlight has fallen on foreign students, who make up the largest proportion of non-EU nationals entering the country and more than half of all net immigration.

That has prompted some conservatives to argue that the UK’s student visa policies are being abused, especially by those bringing dependents into the country. They’re demanding that the numbers be curtailed. It’s an idea that should be scrapped in the new year.

For one thing, foreign students are vital to sustaining the country’s universities. Since UK schools don’t have the large endowments that underpin many of those in the US, they’re especially reliant on tuition payments. Foreigners make up about 22% of total students — more than half at some top London universities — and their fees can be double what locals pay. For many schools, these students are the difference between solvency and shutting the doors. Far from crowding out domestic students, moreover, immigrants cross-subsidize their instruction and research.

There are also economic benefits. A typical foreign student contributes more than £100,000 ($124,000) a year to the UK economy. Those who entered university in 2018 are estimated to have collectively added nearly £30 billion over the course of their studies, far outweighing their cost to public services (of about £2.9 billion). Although most leave soon after graduating, those who stay are hardly freeloaders: Like other working people, they pay taxes, VAT, social security fees and so on.

These contributions are felt around the UK — not just in London and the wealthier southeast — making international students an important part of rebalancing the country’s economy. And for all the benefits brought by higher tuition payments, it’s hard to put a price on the network effects and soft-power impact of so many foreign students returning home with strong British ties. Kicking them out to meet an arbitrary immigration target could hardly be more shortsighted.

Prime Minister Rishi Sunak’s government hasn’t yet clarified its plans. Although officials at the Department for Education have tried to tamp down the idea of new restrictions on foreign student visas, the policy will ultimately be determined by the Home Office, which is currently led by an anti-immigration hardliner.

Some reports have suggested the government’s main focus will be “student dependents and low-quality degrees,” which might seem like a reasonable compromise. In fact, it’s woolly thinking: There’s no evidence that dependents (who are entitled to work) are a net burden on the country,  and a crackdown on foreigners pursuing technical qualifications or “lesser” degrees risks starving lower-tier schools and their local communities of a crucial source of funding and talent, for no good reason.

In a strategy document published last year, the government rightly noted that Britain’s education sector punches above its weight but below its potential. Sunak, who has spoken of his own life-changing experience as a foreign graduate student in the US, should commit to more international students — not fewer. Countries lucky enough to attract foreign students are usually doing something right. Britain should keep doing it.

More From Bloomberg Opinion:

• The US Can’t Afford to Lose Skilled Immigrants: Editorial

• US and UK Should Welcome Talent, Not Drive It Away: Mihir Sharma

• Britain Can’t Look Beyond Oxford for Its Leader: John Authers

The Editors are members of the Bloomberg Opinion editorial board.

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