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Across Europe, the anti-immigration rhetoric is growing louder. Leaders in Germany and France, once seen as stalwarts behind a borderless European Union, have reacted to a rise in support for far-right parties by increasing border controls.

Last month, Berlin introduced greater land border checks in what some observers warned could be the end of the European Union's Schengen Treaty that, in principle, provides for a passport-free area between the bloc's 27 member countries.

France's new interior minister, Bruno Retailleau, said last week that he wanted faster deportations of those who had "broken in" to his country. Until a recent change of government, the United Kingdom was ready to deport asylum-seekers arriving via the English Channel in small boats to Rwanda.

Italy, with its huge coast and close proximity to North Africa and Eastern Europe, has been a popular target for asylum-seekers and economic migrants. Looking to tackle the number of migrants landing on its shores, Italy has signed deals with other countries to help create deterrents, including with Libya in 2017 and Albania in 2023.

Anti-migrant policies are often seen as a trait of right-wing administrations but new research co-authored by a Northeastern University professor shows how even centrist governments have been willing to "blur" their ideology to adopt a harder stance on border controls.

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