Eurosceptics have long suspected it and now we have the proof. The French find nothing as entertaining as British incompetence.

Ken Loach's film, The Navigators, about how privatisation destroyed Britain's railways, was seen as a typically gritty slice of social realism on this side of the Channel, but in France it is enjoying success as a black farce, with 70,000 flocking to see it on its opening weekend.

Even Louis Gallois, head of SNCF, the state-run railway system, attended a special screening at the Paris headquarters of the French rail union, where Loach was given a standing ovation.

While British critics saw it as a grim portrayal of how experience and expertise were junked in the rush to the free market, its French distributors saw its comic potential and hired one of the country's best known cartoonists to design the poster.

Loach, who has a huge following in France after Kes, My Name Is Joe and his Spanish civil war epic Land and Freedom, said he was thrilled at the reaction, especially since the film was only shown on one screen in Britain, without any advertising.

French critics have praised The Navigators' humour and tragedy, and their railway workers were so impressed they presented Loach with a Paris St Germain football shirt with his name on the back.

The film's producer, Rebecca O'Brien, has also been taken aback, admitting they had very modest expectations of the film, which was shown on Channel 4 in November "so it could get the maximum possible audience".

But she denied that its appeal to the French relied on reinforcing Gallic prejudices about backward-looking Britain. "Though I suppose if you do have the best railway system in the world the temptation to gloat must be irresistible."

Nor did Loach detect any note of Gallic triumphalism in its reception. "They are anything but complacent. They are very worried about the contracting out of services for Eurostar, of being contaminated by the kind of practices we have."