A rallying point for refugees, or simply a symbol of how immigration policies have failed?

The rows of blue, white and orange tents stretched out on a dusty concrete floor in a cold aircraft hangar of a building might not seem much like a promised land.

But in spite of its miserable conditions, the Red Cross hostel in Sangatte, outside Calais, has become a rallying point for thousands of refugees from Asia, Africa and Eastern Europe; a bridgehead to a better life.

Opened three years ago to hide the eyesore of desperate refugees sleeping on the streets of Calais, Sangatte has perversely become a highly visible symbol of the failures of the immigration policies of Britain and France. Used for sustenance and shelter, it is a convenient base for many of its 1,300 desperate residents to make daily attempts to board trains crossing into Britain.

Television footage of these forays – often involving hundreds of asylum-seekers scaling fences and charging security guards – have provided potent material for politicians seeking to exploit public fears over international migration.

Claire Doole, London spokeswoman for the United Nations High Commissioner for Refugees, said: "We do accept that the centre, as it is, is causing a lot of problems, particularly from the image it gives of refugees."

The impression given is that Britain has become the "Holy Grail" for asylum-seekers and that France is happy to ignore its responsibilities and pass on the problem.

The reality is far more complicated. Asylum applications to Britain are higher at 71,700 but fell 11 per cent last year, compared with a 22 per cent increase in claims in France. The 53,875 asylum-seekers applying in France came mostly from Turkey, Iran, Democratic Republic of Congo and Algeria.

Cultural distinctions often separate the Sangatte residents from this group. In the main, those living at the Red Cross centre are Afghans and Iraqi Kurds.

Jean Candler, of the Refugee Council, said: "Those are both communities that are well-established in the UK. They are also more likely to speak English than French as their second or third language."

Others choose to come to Britain because they know that their claims of non-state persecution (such as attacks by political extremists, racists or homophobes) will be ruled ineligible in France and Germany.

Despite the perceived tolerance of Britain and its duties under the UN Convention on Refugees 1951, the political sensitivities around immigration have ensured an official policy devised to keep asylum applications at a minimum by making it as difficult as possible to enter the country.

The result is that thousands of asylum-seekers are holed up in Sangatte, plotting their routes across the Channel.

The French authorities declined to regularise their immigration status or invite them to apply to stay in France. The minimal attempts by French police to prevent Sangatte residents boarding British-bound trains at the nearby Frethun yard have also been derided.

British politicians argue that the French government's failure to insist that the Sangatte refugees make their claims in France is an abdication of its obligations under the Dublin Convention, which requires asylum-seekers to apply for help in the first EU state in which they arrive.

French officials say most of those at the Red Cross centre will have entered the EU from Italy, Germany or elsewhere and are not France's responsibility. But the political capital made by the French far-right from public fears over migration mean that Sangatte, and its shocking images of an immigration system in chaos, cannot continue.

Keith Best, of the Immigration Advisory Service, said Britain must be allowed to deploy immigration staff on the French side of the Channel to allow genuine refugees to be brought safely to the UK while handing failed applicants to the French authorities.