The former chief of the British Border Force has warned the country will face a “crisis” level of illegal migrant crossings of the English Channel if Britain and France fail to come to an agreement to have boat migrants immediately returned to France.

The former head of UK Border Force, Tony Smith, said asylum seekers attempting to come to the United Kingdom from France must apply for asylum on the French side of the English Channel, and that the two governments need to sign a treaty that would see boat migrants brought back to France rather than onto British shores.

“What I’m advocating is that we need to try as best we can to replicate the juxtaposed controls for legitimate applicants in the same way as for illegitimate applicants,” Smith told the Daily Mail.

“If they want to come to the UK they need to make their case on the French side, and if they are found in the waterways or even make it as far as Dover we say ‘I’m sorry but you go back there and that’s where you will be interviewed and processed, on the French side’,” he added.

Mr Smith said that he was unsure if Priti Patel’s Home Office will be able to “make the breakthrough” with France, but did note that the British government has come to agreements with the French in the past.

“I think there are potentially opportunities but there will have to be some kind of a quid pro quo which would satisfy the French that this was a measure that was designed to help both parties, not just a one-way street where the UK essentially is able to blockade anybody coming over from France,” the former Border Force chief said.

The London-based think tank Migration Watch UK projected that if the current trend continues an estimated 7,500 illegal boat migrants will reach Britain by Christmas.

The call from Tony Smith backs up similar statements from the former Prime Minister of Australia, Tony Abbott, who was able to successfully halt illegal boat migration from Asia with his Operation Sovereign Borders policy seven years ago. The policy mandated that illegal migrants be turned back to the country they came from or to a third country where asylum seekers would be processed and legitimate refugees placed in safe countries other than Australia at Australia’s expense.

This effectively ended Australia’s issues with boat migrants, by eliminating the incentives for travelling to the country by sea.

In May, Mr Abbott said: “The French have no right to wave-on their problems to Britain just because they are unwilling or unable to control their own borders.”

“Plainly, this will require a degree of determination and planning on Britain’s part. The French may not like to hear ‘they shall not pass’ from Britons… Still, in the long run, this is for France’s good too; as the only way to clear the camps in Calais is to ensure that none of their occupants can ever get across the Channel and stay,” he said.

The former Prime Minister went on to warn that if such a policy is not implemented then the “trickle” of boat migration “quickly become a flood” as was seen during the European Migrant Crisis of 2015, which saw millions of migrants pour into the bloc.

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