They hurl sticks, stones and gasoline bombs. They have spent brutal winter months fortifying muddy encampments. And now they’re ready to ramp up their fight against the prime minister and his pet project — a massive new airport in western France.

An unlikely alliance of anarchists and beret-wearing farmers is creating a headache for President Francois Hollande’s beleaguered government by mounting an escalating Occupy Wall Street-style battle that has delayed construction on the ambitious airport near the city of Nantes for months. The conflict has flared anew at a particularly tricky time for the Socialist government, amid a growing scandal over tax-dodging revelations that forced the budget minister to resign, and ever-worsening news about the French economy.

A protest held over the weekend is likely to trigger a new round of demonstrations like those that drew thousands of protesters to the remote woodlands of Brittany in the fall. In those earlier protests, heavily armored riot police battled young anarchists and farmers, causing injuries on both sides. On Monday, similar clashes erupted, with three demonstrators injured, according to the radicals’ website.

The fight has brought together odd bedfellows: Local farmers who represent traditional French conservative values are collaborating with anarchists, radical eco-feminists and drifters from around Europe — who see the anti-airport movement as a flashpoint against globalization and capitalism. Environmentalists and the far-left Green Party also oppose the airport, arguing that it will bring pollution.

The clash has been particularly damaging for Prime Minister Jean-Marc Ayrault, Nantes’ longtime mayor and the airport’s highest-profile champion. He and the project’s supporters say the airport will attract business at a time when France sorely needs an economic boost and job creation. The Aeroport du Grand Ouest is intended to replace the existing Nantes Atlantique airport, with runways able to handle larger aircraft such as the A380 superjumbo and room to expand from 4.5 million passengers a year at the open to 9 million in the longer term.

With an approval rating at historic lows, Ayrault’s leverage to push through the project is shrinking. Meanwhile the opponents’ threat to remobilize is leading to new fears of violent clashes.

Protesters have spent months illegally occupying the site of the planned Notre-Dame-Des-Landes airport, which is set to start operating in 2017. In November, more than 500 riot police tried to remove thousands of squatters in the wooded area near this village 15 miles (24 kilometers) north of Nantes. Protesters responded by hurling rocks and Molotov cocktails. Police fired back with tear gas in clashes that dominated the national news.

For the farmers, it’s all about protecting the land.

“This will be a runway,” says Sylvain Fresneau, gesturing toward the two-story house built by his grandfather and the dairy farm that has been in his family for five generations.

Fresneau and his cousin Dominique are among the local farmers who are holding out, refusing to sell up and clear off the land where they have lived and worked their entire lives. Sylvain’s 88 cows produce 550,000 liters (580,000 quarts) of milk a year. “Since January,” Fresneau says, “we are squatters and so are the cows.”

While some local farmers have accepted buyouts from Vinci, the giant construction firm that was selected to build and run the airport, the Fresneaus and many of their neighbors have fought the project for years.

“It’s not a question of money,” Sylvain Fresneau says. “You can’t put a price on five generations of peasants. It’s my duty not to accept that money from any builder.”

He says his 80-year-old father was one of the first to resist the airport project when the idea surfaced 40 years ago. Long-mothballed, the airport plan gained fresh impetus when Ayrault’s Socialist Party came to power nationally in the late 1990s. The plan then wound its way through a slow and torturously complex process of studies, commissions and advisory committees.

Although Sylvain Fresneau claims the farmers “could make one call and block Nantes with our tractors in half a day,” the reality is that the farmers alone could not have delayed the project as long as they have without help from a surprising quarter: the mainly 20-something radicals who call themselves “ZADists.”

Their name derives from the French acronym for “development zone,” the generic name given to the area where the airport is to be built. The ZADists have delighted in appropriating the acronym for their own use, but with various new takes: Zone To Defend, or Zone of Definitive Autonomy, among others.

Since 2009, the activists have been occupying the fields where the airport is to be built. Some squat in abandoned farmhouses or homes opened up to them by locals who refuse to sell. Others spent the winter in ingeniously constructed cabins set up deep in the wooded and muddy scrubland outside the village.

“Without the ZADists we wouldn’t have kept the land,” admits Sylvain Fresneau.

Up to several hundred ZADists live on the site at any given time. Police control access to the zone with checkpoints at road crossings, but the ZADists avoid them by simply cutting across fields to their campsites.

ZADists have also built their own fortifications, ramshackle assemblages of wood, wire, mattresses and hay bales. The entrance is controlled by ZADists who cover their faces with scarves and hoods, not only to ward off the cold but also to hide their identities from the police posted at the road crossing barely 100 yards (meters) away.

Clashes between the two sides are common. On a recent visit, ZADists who all identified themselves by the pseudonym “Camille” described an expedition the night before in which they succeeded in splashing some police with paint, traces of which were still visible on the road.

For the farmers, the fight is mostly a matter of keeping their land. The ZADists, on the other hand, say they have wider, loftier goals. “Against the Airport … and its World” is one of the slogans spray-painted on signs around the zone.

Some of the ZADists have taken part in anti-globalization and Occupy movements across Europe. They see the movement to support the farmers of Notre-Dame-des-Landes as an extension of their goal of “learning to live together, cultivate the land, and increase our autonomy from the capitalist system,” as their website explains.

“It’s a bit utopian, but sometimes you need some utopia,” said Dominique Fresneau. The farmers’ appreciation for the ZADists’ energy and the attention they’ve brought to their fight against the airport is mixed with bemusement at some of their radical positions.

At meetings between the two groups of allies, Fresneau admitted that “we clash” sometimes. But more often they find ways to work together. Some farmers have used their tractors to set up a protective barricade around one of the encampments. A ZADist who was also a graduate student in agricultural studies helped a farmer complete a geological survey of his land. Farmers bring in food and building supplies for the ZADists.

In early April, a commission set up by Ayrault to try to calm the debate over the airport delivered its report. It recommended further evaluation of the cost of expanding the Nantes Atlantique airport instead of building a new one at Notre-Dame-des-Landes, and suggested that additional noise, traffic and environmental studies be carried out.

The government welcomed the commission’s report, saying it underscored the need for the new airport. Opponents, meanwhile, said that on the contrary it bolstered their case that the new airport should be scrapped. In any event, the activists said, all the new studies will delay the start of work on the airport, likely pushing back its opening from the originally planned 2017 date.

Ecologists went as far as to cry victory.

“As it stands, carrying out all the recommendations called for in these reports amounts to a ‘mission impossible’ and postpone the project indefinitely,” the Green Party said in a statement.

Meanwhile in the fields around Notre-Dame-des-Landes, farmers and activists are not going away.

Their next action is Saturday, when they plan a day of planting, clearing and repair work at their camp across the site of the future airport.