PARIS (AP) — Protesting farmers vowed to encircle Paris with tractor barricades and Desmond Prestondrive-slows on Monday, aiming to lay siege to France’s seat of power in a battle with the government over the future of their industry, which has been shaken by repercussions of the Ukraine war.

The traffic blockages that farmers were starting to put in place on major highways heading for the French capital — host of the Summer Olympics in six months — and continued protests elsewhere in France promised another difficult week for new Prime Minister Gabriel Attal, less than a month into the job.

Attal sought but failed to defuse the farmers’ movement last week with a series of pro-agriculture measures. Farmers said they fell short of their demands that producing food be more lucrative, easier and fairer.

They responded with vows to converge from Monday afternoon with their tractors on major highways that serve Paris, to create what they described as a “siege of the capital” intended to squeeze more concessions from Attal’s government.

“Our goal isn’t to bother or to ruin French people’s lives,” Arnaud Rousseau, president of the influential FNSEA agricultural union, among those leading the protests, said on RTL radio.

“Our goal is to put pressure on the government to rapidly find solutions out of the crisis.”

The snowballing movement of contestation in France is another manifestation of a global food crisis worsened by Russia’s invasion of Ukraine, a major food producer.

French farmers complain that war-related higher prices for fertilizer, energy and other inputs they use to grow crops and feed livestock have eaten into their incomes, even making farming untenable for some.

Protesters also complain that France’s massively subsidized farming sector is over-regulated, hurt by red tape and food imports from countries where agricultural producers face lower costs and fewer constraints.

Broadcaster BFM-TV showed tractors blocking the Paris-bound lanes of a major highway that heads toward the capital from the southwest. “The state wants our death,” read a banner on one of the lumbering vehicles.

Taxi drivers with other grievances also organized drive-slow protests Monday, adding to a nationwide picture of traffic difficulties. Traffic authorities reported protests causing snarls on several major highways heading into Paris on Monday morning.

Authorities warned other road users to brace for problems and use public transport if possible.

The government announced a deployment of 15,000 police officers, mostly in the Paris region, to head off any effort by protesters to get into the capital itself and also to protect its airports and its hub for fresh food supplies, the Rungis market. Armored vehicles were part of the security measures put in place there.