Telegraph.co.uk: Calais mayor threats to open France's borders and allow thousands of migrants into Britain

Ms Bouchart did not say which laws she was referring to specifically, but has previously called for the scrapping of the Le Touquet Treaty, which lays responsibility for border controls on the French side.

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A network of smugglers is believed to be charging migrants at Calais' largest camp, known as "the Jungle," up to €7,000 (£5,000) in exchange for passage across the border to Britain.

Migrants make their way towards the Channel Tunnel   Photo: EPA

A Home Office spokesman said the UK would continue to work closely with the French government to tackle the situation but added: "We must also treat the causes of this problem, not just deal with its consequences.

"That's why the UK is playing a leading role in pushing for action through the EU and the UN to tackle the causes of illegal immigration and the organised trafficking gangs behind it."

The spokesman pointed out how much the UK had provided adding than since 2014, there has been an additional £12 million to reinforce security at the juxtaposed border, a £2 million upgrade of detection technology and a £1 million extension of dog searching capacity.

There were also reports on Thursday that those unable to pay the smugglers' fare were resorting to prostitution to pay their way into Britain.

Earlier this week a member of one of the gangs - who is believed to be a British ringleader - threatened Ukip MEP Mike Hookem with a pistol as he visited the camp near Téteghem.

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Ms Bouchart's remarks came as a French mayor whose town is at the centre of the migrant crisis demanded that British police join forces with their French counterparts to arrest the UK-based smugglers terrorising his community.

Franck Dhersin, the mayor of Téteghem, said British police were failing to take their share of responsibility for the gun-wielding "English mafia" who are based in a migrant camp a few miles away from his town.

And residents in nearby villages have told The Telegraph they have resorted to using guard dogs and building a seven-foot wall to ward off smugglers and migrants.

"The British police never contact us about this situation, unlike the Belgian police who are constantly in touch with us and frequently cross our borders to help seize these cars and to try and tackle the problem," Mr Derhsin said.

A migrant smokes a cigarette near the Channel Tunnel   Photo: EPA

"It is crucial that this operation is a joint effort between French and British police, but that is just not what is happening right now.

"Instead we have the cars driving around my town without any shame and no one has been able to arrest them. It just cannot go on like this,"

Mr Dershin, who has himself been threatened at gunpoint by the camp's smugglers, said the reputation of both police forces was threatened by a lack of co-operation.

"It depends upon the reputation of both British and French police that we share information and we share resources also,” he said.

"I have no doubt that the public's opinion in England, as in France, is that these British criminals must be stopped immediately. We all want the same thing, but there is no cooperation at present from the British side.

"I would urge the British police to come to France and meet us to help work on this issue.

"I suppose the reason they do not come and see us as much as the Belgians do is because they have to take a ferry to get here, instead of simply driving across the border.

"We can only stop these criminals if we co-operate and work as a single operation with help from both sides."

A migrant climbs over a fence to get to the Channel Tunnel   Photo: EPA

It comes as French villagers in the Calais area revealed they have hired extra security after intimidation from smugglers and migrants.

One 48-year-old man told The Telegraph he had resorted to spending £1,800 on a seven-foot-high wall to stop migrants hiding from the police in the trees outside his house.

Ludovic, whose house in western Calais overlooks a stretch of railway, said: "Every night the migrants come down here to try to get onto the railway tracks.

"I have quite a few large trees in my garden and the migrants were running in and hiding when chased by police."

"I had a two-metre wall put up to stop them. It cost me €2,500 which is quite a lot for me but I need to improve my security.

"This problem has been going on for too long. It's dangerous because you don't know who is about. The crisis is very much a shared problem and I think the British police should be over here helping."

Madeleine Darneux, 39, said she felt threatened by smugglers who loitered near her home in the picturesque village of Fréthun in luxury cars with black-tinted windows.

"I am fortunate as I live just off the road from the railway so I only see the migrants running across the fields and tracks.

"But I am a little intimidated by these cars with English numbers plates that are here at night, and speed past at all hours, with the black windows.

"I have a guard dog who barks very loud and would bite them if they tried to come in here.

"The migrant issue is a humanitarian issue, I do not want to criticise them because they are only coming here because they are desperate," she added.