Britain and France on Sunday urged other European Unionstates to help them tackle the growing crisis in northern France caused by thousands of migrants seeking to make illegal and dangerous crossings into England.

The French port of Calais has become a focal point for the huge influx of migrants entering Europe to escape poverty and violence in the Middle East and Africa.

Nightly attempts by large groups of the estimated 5,000 migrants in Calais to force their way through the rail tunnel linking France and Britain have provoked public anger and severely disrupted the flow of goods between the two countries.

"There are no easy solutions – and it is not for the UK and France to solve these problems alone," Home Secretary Theresa May and her French counterpart Bernard Cazeneuve said in a joint letter published in the Sunday Telegraph.

"Many of those in Calais and attempting to cross the Channel have made their way there through Italy, Greece or other countries. That is why we are pushing other member states – and the whole of the EU – to address this problem at root."

Several people have been killed trying to enter Britain, where they believe they have better prospects of a new life.

The joint plea came as Britain, where the crisis is heaping pressure on Prime Minister David Cameron to take action, detailed some of the extra security measures agreed with French President Francois Hollande on Friday.

Cameron's office said Britain would fund a significant boost in the number of private security guards patrolling the French entrance to the Eurotunnel-operated under-sea rail link. New fences, security cameras and infra-red detectors would also be used to improve security.

French authorities have already increased the number of police in the area.

The official response to the crisis was on Sunday criticized as lacking humanity by Church of England Bishop Trevor Willmott, whose diocese covers the English side of the 30 kilometer (18.64 miles) sea channel separating the countries.

"We've become an increasingly harsh world, and when we become harsh with each other and forget our humanity then we end up in these stand-off positions," Willmott said in an interview with the Observer newspaper.

Britain and France said their efforts were not limited to beefing up security, and that they had led efforts to break up the criminal gangs who seek to profit from the flow of migrants.

"Ultimately, the long-term answer to this problem lies in reducing the number of migrants who are crossing into Europe from Africa," May and Cazeneuve wrote.

"Many see Europe, and particularly Britain, as somewhere that offers the prospect of financial gain. This is not the case – our streets are not paved with gold."