(Bloomberg) -- French farmers drove hundreds of tractors to Paris to protest a European ban on controversial pesticides that threatens sugar output, as well as other agricultural regulations.

France has backtracked on a plan to allow the continued use of neonicotinoids — a type of pesticide considered harmful to bees — after last month’s European Union court ruling against such exemptions. Growers say that the ban and implementation of other environmental measures will make crop production more difficult.

Growers’ groups warned that without the use of such insecticides, harvests could face big losses from issues like crop viruses. That could worsen the region’s sugar deficit and leave it more reliant on imports. It’s another headache for farmers already being hit by high fuel and fertilizer prices that are squeezing their margins.

Several farmers in France, a major European sugar producer, said that despite the risk they have no option but to plant untreated seeds in the coming months because they’re already contracted to.

“The alternatives to neonicotinoids that we have in France right now had a limited impact in 2020,” said Benoit Carton, a farmer in the Seine-Maritime region of northern France. “The priority today is to reassure worried farmers and to present a compensation plan that will compensate them as soon as they see their first losses.”

Even before the recent European court ruling, French sugar-beet yields were expected to drop by 5% to 7% for the coming 2023-24 season due to smaller plantings, according to Francois Thaury, an analyst at Paris-based adviser Agritel. Losses, while hard to predict, could now reach 10% or more, he said. 

Some growers at the protest on Wednesday said they had already signed five-year contracts and would likely face financial repercussions if they cut plantings. Research on alternative treatments and genetic modifications isn’t yet conclusive, they said.

Sugar producers such as France’s Cristal Union have raised prices for beets bought from farmers to encourage sowing and help cushion them from losses. 

“Farmers are being asked to plant beets without any guarantees on potential losses,” said Henri Faes, deputy director of beet farmer group CGB’s branch in Oise. “There’s a risk that we’ll lose farmers and that we’ll have a lower volume of sugar.”

(Updates with comments from growers in seventh and ninth paragraphs.)

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