Sally Hunt, general secretary of the University and College Union, said: "The UK remains one of the most popular destinations for foreign students because of our proud international reputation for excellence and we need that to continue.
No matter how this is dressed up, the damaging message that the UK deports foreign students studying at UK universities will reach all corners of the globe.
"Foreign students bring in billions of pounds every year, but the benefits are not merely financial.
"UK students profit enormously from exchange programmes with foreign universities and also through mixing with, and working alongside, students studying here."
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