Migrant deal with France comes to screeching halt after last-minute talks with Labour go nowhere

One French minister, Xavier Ducept, claimed putting a cap on boat crossings would be "extremely complex - and that’s putting it diplomatically".

Mr Ducept also claimed it would be "dangerous" for France to accept responsibility for the migrants, despite them being in France.

Even without a cap, France's border guards have refused to intercept boats because of how they interpreted international law.

And critics including the Shadow Home Secretary pointed out that even if the boats were seized, the would-be migrants themselves were let go to attempt to cross another day.

France intercepts just a third of attempted crossings at present - a drop from more than half in 2023, when the three-year deal was signed under Rishi Sunak.

That deal, which is now over, saw France handed £475million to increase the number of officers on its northern shores.

Discussions are also said to have hit a wall over how Britain would release a funding package worth around £650million to to France over the next three years.

However, it is understood that "procedures" were put in place for if Britain and France failed to reach a deal by Tuesday night.

These are said to ensure there was no "cliff edge" loss of enforcement while negotiations continue.

Ms Mahmood wants to link the next three years of funding to an increase in interceptions and more regular updates on how many interventions have been made.

Mr Sunak's 2023 deal included plans for a new detention centre in Dunkirk.

That was meant to have been built by this year, but was delayed by planning problems.

The Home Secretary is reported to want to force France to finish the centre before any further negotiations can continue.

Either way, a French interior ministry source explicitly told Le Monde yesterday that the talks had "failed".

"Everything has gone up to the ministerial level," the source added, which the Home Office denies.

Mr Ducept unleashed a string of attacks on Britain's demands last week.

"Giving an interception rate on boat numbers seems quite illusory... because it'll always be hard to say how many boats we dissuaded from leaving, how many smugglers from acting.

"What we want is for the British to contribute to funding interception systems, which are very expensive - but they must not condition them on an 'efficiency' form that could be extremely dangerous for migrants and our services because it's France bearing responsibility.

"We want to keep principles: rescue first, and the law - acting in a legal framework allowing safe operations for migrants and personnel."

Reform UK's home affairs spokesman Zia Yusuf told GB News yesterday: "The French are laughing at us. Hopeless Tory and Labour governments have paid them £700 million of British taxpayer money to stop the boats, yet illegal boat crossings skyrocketed."

A Home Office spokesman said: "France is our most important migration partner and together our joint work is bearing down on small boat crossings.

"We have prevented over 40,000 crossing attempts by illegal migrants since this Government took office."

Turning to the "one-in, one-out" deal, which has seen 377 people sent back to France in return for 380 migrants sent to the UK, the spokesman added: "Our landmark deal means illegal migrants who arrive on small boats are being sent back to France."