Hundreds of farmers have travelled to the French capital Paris by tractor to protest over the struggles of the farming community and to put pressure on supermarket chains to pay them more for their produce.
Some 340km of tailbacks were reported during morning rush hour as convoys of the vehicles caused traffic tailbacks on the main roads into the city.
Tractors also blocked traffic in Lyon and other cities.
In Paris, around 200 farmers blocked the Champs-Elysees - the main avenue - and dumped hay outside Fouquet's restaurant, a favourite of the rich and famous, which was ransacked earlier in the year by "yellow vest" protesters.
"We demand to see the president. We will stay as long as is necessary," Cyril Milard, a member of the FDSEA farmers' union told a rally.
Some had signs reading "Macron, answer us!" attached to the front of their tractors.
French farmers have for years been complaining of difficulties making ends meet.
Mathieu Garnotel, a farmer with a 130-hectare property in the Marne region, said that one in three farmers in his community was running a loss or just breaking even.
He blamed falling farm prices and the scrapping of sugar quotas along with higher costs and anti-pollution taxes. "We are stuck between a rock and a hard place," he said.
The protest comes as supermarket chains and food producers begin annual price negotiations.
A new law attempts to tilt the scales, which are heavily weighted in favour of big supermarket chains, back in the farmers' favour by giving them more of a say in pricing.
But the farmers say they have yet to see the benefits.
They have also hit out at "agri-bashing" by animal rights activists and environmentalists, including bans on synthetic pesticides implemented by dozens of small towns and villages.
Agriculture Minister Didier Guillaume expressed solidarity with the farmers.
"I support the anger of the farmers and this demonstration. The belittlement has gone on too long," he told Europe 1 radio.
