Britain plans to create a ‘secure zone’ at the French port of Calais to protect lorries heading for England from migrants trying to enter the country illegally, Interior Minister Theresa May said yesterday.

Migrants fleeing war, political turmoil and poverty make daily attempts to board lorries and trains heading for Britain, drawn by family ties, a growing economy and a perception that the British system treats migrants better than other countries.

The problem has been exacerbated in recent weeks by a French ferry workers’ strike that blocked traffic around the port. British police yesterday raised their estimate of the number of migrants in Calais to 5,000 from 3,000.

May said the secure waiting area would hold 230 vehicles, the equivalent of a four-kilometre queue of traffic.

“This should transform protection for lorries and their drivers – removing them from the open road where they can become targets for migrants attempting to board their vehicles,” May said in a statment to Parliament.

She said that over 8,000 attempts by illegal migrants to enter Britain were successfully intercepted by border authorities between June 21 and July 11. Her office said the zone would be policed by French authorities and was expected to be operating before December. It would replace an existing 90-lorry waiting area, and be set up behind established fences, which French and British authorities are working to improve.

But the plan was not seen as a permanent solution by trade organisations and Eurotunnel, the company operating the rail link under the channel.