The cost of spoiled loads as a result of stowaways getting into UK-bound vehicles could be as high as £1bn a year, the RHA has estimated.

Assuming an average value of £30,000 per trailer, that total could be reached if just 1% of the 10,000 loads crossing the Channel every day were tampered with, said RHA chief executive Richard Burnett. “That is a massive and unacceptable cost to our economy and many hauliers are having to absorb large parts of that cost,” he said.

FTA deputy chief executive James Hookham said it was impossible to estimate the exact cost to the industry of spoiled loads as values could range from just a few hundred pounds per vehicle to millions in the case of pharmaceuticals, but he agreed the economic effect was “significant”.

While goods-in-transit insurers should ultimately be paying for the damage, said Hookham, many claims were being rejected as a result of exemptions in policies for the kind of civil unrest being witnessed in Calais; while in other cases, insurers were only paying out for those parts of the load that were obviously damaged, even where entire loads were being destroyed as a precaution.