“Put plainly, this means that, to be considered valuable to the country as a whole, immigration should benefit not just the migrants themselves but also make existing residents better off,” the paper says.

It proposes measures to drive down the number of lower-skilled EU migrants – offering them residency for a maximum of only two years, in a document likely to cheer hardliners in the Tory party. Those in “high-skilled occupations” will be granted permits to work for a longer period of three to five years.

The document also describes a phased introduction to a new immigration system that ends the right to settle in Britain for most European migrants – and places tough new restrictions on their rights to bring in family members. Potentially, this could lead to thousands of families being split up.

Leaked document reveals UK Brexit plan to deter EU immigrants