It comes in the wake of the attempted bombing in Liverpool by a failed asylum seeker who was still in the UK seven years after his application was first rejected. Emad al-Swealmeen is understood to have had mental health problems that were exacerbated by the drawn-out process.

Speaking on a trip to the US, Ms Patel hailed Greece for taking a “very different” approach to that of the EU, including the controversial “pushback” tactics of turning boats back at sea.

“They have not decided to sit behind the EU block of competency,” said the Home Secretary, who earlier this week launched an attack on the EU’s open borders – the Schengen zone – for fuelling a “mass migration crisis” that has spurred a record surge in illegal Channel crossings.

More than 24,500 migrants have reached the UK already this year – nearly treble the total for the whole of 2020. That figure includes more than 5,000 in November, the highest monthly total ever, despite colder weather and riskier sea conditions.

In an exclusive interview with The Telegraph, Kyriakos Mitsotakis, the Greek prime minister, backed calls for tougher controls and warned that freedom of movement in the EU would be “finished” if leaders failed to ruthlessly protect the bloc’s borders.

“We will not just throw open the doors and let the migrants in,” he said. “EU leaders know that if that happens then Schengen is finished. Freedom of movement is finished. 

“Countries such as Sweden, Denmark, the Netherlands and others will simply throw up the borders. We need strong external borders.”

Alexander Lukashenko, the president of Belarus, has lured thousands of migrants from countries such as Iraq before forcing them to the borders with EU members Poland, Latvia and Lithuania. The situation on the border with Poland has reached crisis point in the last fortnight.