we hope to get the number of illegals using this route down to zero

British embassy official

The new rule was introduced as Home Secretary David Blunkett announced an end to fines imposed against Eurotunnel when illegal immigrants are discovered on its freight services.

The prime minister's official spokesman said rail companies SNCF and EWS would also have the threat of penalties lifted, as they had done all that could be expected of them to deter stowaways.

Passport controls

Before the new controls were introduced, asylum seekers intending to reach Britain were able to buy tickets for Calais at the Gare du Nord station in Paris.

The new Eurostar law required an act of parliament

Because they apparently were not intending to leave French territory they could avoid all passport controls.

They then stayed on board through the tunnel and either disappeared or sought asylum upon arrival at Waterloo station in London.

In recent months the number of illegal immigrants reaching Britain via Eurostar had fallen, after British officials were allowed to start screening passengers in Paris.

An embassy spokesman said: "Now we hope to get the number of illegals using this route down to zero."

The new measure, agreed at a Franco-British summit a year ago, means British immigration officials operating at the Gare Du Nord will have the right to question anyone, even travellers who say they are merely moving between two points within France.

Before that could happen an act of the French parliament had to come into effect, because it was seen as a serious matter involving a derogation of national sovereignty.

Security

Growing numbers of illegal immigrants choosing Britain as their favoured destination led to harsh criticism of security surrounding the Channel Tunnel.

Train operators have been forced to increase patrols at goods yards to stop asylum seekers hiding on board.

And on Friday Eurotunnel failed in a new bid to have the Sangatte refugee camp closed.

The Red Cross-run camp is just two kilometres from the tunnel entrance and it is claimed the proximity is adding to the number of asylum seekers trying to beat its security.