”Okay, off you go.” On the set of a film by Ken Loach, formalities are kept to a minimum. Nobody shouts: “Lights ... camera ... sound ... rolling!”

In the garden of a pub in the East End, Loach is orchestrating a pay dispute. On one side, 20 extras of indeterminate nationality are shouting at, on the other, a short peroxide blonde in leather. The camera turns for about two minutes, and a babel of voices surges, the men’s guttural and accented, the woman’s forceful and estuarine. The gist of the scene is that she owes them money, but is breaking the news that she doesn’t have any.

“Okay, let’s stop there.” Loach steps into the throng and, helped by a Polish translator who is also one of the actors, starts to prod. “Not everybody has to speak the whole time,” he explains. There’s another take, more commotion, then: “Just a few little things to change.” As takes three and four come and go, subtle tweaks are sculpted into the action. “Everyone’s doing really well.” He barely raises his voice. Take five. “We’ve got some really terrific stuff. Just one more.” Six. “Last time, I said it was the last one. I was lying. We had one smiler. I think nobody’s happy.”

Loach is an evergreen 71. Much of his work from 40 years on film’s political front line is being released in a two-box set of 16 titles. If the totality of it could be summed up in a phrase, that one would be as good as any: nobody’s happy. His advocates are always outraged that his very British strain of miserabilism finds much less favour here than abroad. Take The Wind That Shakes the Barley, a portrait of the schism within Ireland’s nascent republican movement, but also a distillation of Loach’s core belief that there is a brutality at the heart of the British Establishment. The Palme d’Or winner at Cannes in 2006, it was his splashiest success to date. In France, more than 300 prints were ordered; in Italy and Spain, more than 100. Here, just 40.

Loach’s father, a factory electrician who lived just long enough to see Kes, predicted in 1967 that his son might be a prophet without honour at home. He attended the premiere of Poor Cow, a rare instance of adaptation by Loach. “He obviously didn’t know what to say afterwards,” Loach recalls, “and the only thing he could say, rather gnomically, was, ‘It’ll do very well in Japan.’ He’d never been to Japan or anywhere near it. And I didn’t ask why.”

It’s not just the exoticism of Loach’s drab working-class lives that has enhanced appeal for the rest of the world. Surely it’s also the schadenfreude. But his continental audience may find his latest film less comforting than usual. It’s a Free World..., with its bitterly sarcastic title, confronts the issue of the free migration of labour across European borders. “It’s a disaster in many respects,” Loach comments. “The engine is the search for cheap labour and the hypocrisy of the right wing, which, on the one hand, says ‘Get the foreigners out of the country,’ then, on the other, says, ‘Oh, we need them for the economy.’ They mean they want cheap labour.”

So far, so Ken. The decline of job security has previously furrowed his brow in RiffRaff and Bread and Roses. But anyone expecting him to take up cudgels on behalf of the disenfranchised, the way he did in Cathy Come Home, is in for a surprise. “Our first thought was to follow a group who come and are exploited. Then we thought, that’s a bit predictable – people will say, ‘Here they are championing the downtrodden again.’” Loach and his regular scriptwriter, Paul Laverty, have instead chosen as their protagonist a woman who runs an employment agency. They’ve loaded the dice in Angie’s favour – made her a single mother, the victim of sexual harassment and, as played by Kierston Wareing, immensely charismatic. But nothing can shroud the fact that, in her efforts, to keep her agency afloat, she becomes one of the least sympathetic characters Loach has put at the heart of a film.

“It’s a slippery slope,” he agrees, “and she does do some terrible things, but we wanted to draw the audience into those choices to see why she makes them. She’s very much a child of her time. She has grown up in a world where everything is the deal. Without knowing it, she represents the idea that society advances by everybody pursuing their own interests ruthlessly. She’d be a riot on Alan Sugar’s programme. We just thought it would be interesting to have a protagonist who, for all her abilities and the fact that she’s really likeable, is the agent of exploitation.”

With a small budget and no star, It’s a Free World ... finds Loach also in the grip of market forces. The BBC drama department may have been the crucible in which his political aesthetic was formed in the 1960s, but this is his first film for British television since The Navigators, in 2001. Back then, he was pretty grouchy about having to slum it on the small screen. This time, he’s more sanguine. “I’ve never claimed to be an auteur. God help me. But you labour hard on framing and light and the rhythm of the scenes and the momentum within a sequence. And, of course, it’s much better in the cinema. You regret that a lot of people won’t see it like that. But every few years, it’s not a bad idea to be on television first, because we might get new viewers.”

Another unspoken benefit is the avoiding of British film critics. In Loach’s view, they “judge a film in market terms. By and large, they don’t feel film is a medium to take seriously. I’ve thought about it for many years and I don’t know why it is. When you’re putting a film together, you talk about the politics of the family and try to work out the balance of the relationships and the interplay with social or historical things, so in your head there’s a complex network of ideas, and the reviews you get don’t dig into it at all. That’s what’s depressing”.

The Ken Loach Collection is released on DVD by Sixteen Films on Sept 3; It’s a Free World ... is on Channel 4 next month

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