Marine Le Pen’s globalist rival in the French presidential elections, Emmanuel Macron, has promised to rip up border controls in France, potentially opening Britain up to a new wave of illegal migration.

The establishment favourite in the French presidential race asserted that the Le Touquet treaty, under which Britain operates border controls in the migrant hotspot Calais, should be “back on the table.”

In an interview with TF1, the former Rothschild banker said the deal “must be renegotiated, especially the parts that deal with the fate of isolated child migrants.

“There is no easy solution to the migrant crisis. If there was one, it would have been found.”

Downing Street is likely to be concerned by the statement, as Macron had previously sworn to keep the migration agreement in place just two months ago, in talks with Prime Minister Theresa May.

He said, “If there was a simple answer [to Calais’ migrant crisis], it would have been found. I want to put the Touquet treaty back on the table and to renegotiate the agreement.”

A Downing Street spokesman said, “We have always been very clear that protecting and enhancing the shared border between the UK and France at Calais is in both the UK and France’s best interests.”

A conservative spokesman said, “This just shows that we need the strong and stable leadership of Theresa May, and why voters need to give her the best possible hand to negotiate in Europe.”

“We have always been very clear that protecting and enhancing the shared border between the UK and France at Calais is in both the UK and France’s best interests. By contrast, Jeremy Corbyn is not strong enough to keep our borders secure.”

French sociologist and writer Mathieu Bock-Côté has warned that Macron embodies “all that France wants to extricate itself from.”

“Excessive globalism and cultural leftism are in contradiction with the aspirations that seem to come from the depths of the country,” he wrote in Le Figaro.

The frontrunner in the election, Macron has previously declared that Europe has “entered a world of great migrations” inescapable for the continent, and which will only accelerate.