Hundreds of Greek farmers, some riding tractors, demonstrated in Athens on Friday, demanding more tax breaks and subsidies to combat skyrocketing fuel and fertilizer prices since Russia’s invasion of Ukraine.

Farmers who staged weeks of protests earlier this year over high energy prices say their costs are so high that they will be forced to produce less and raise consumer prices.

Since September, the government has spent approximately 3.7 billion euros ($4.08 billion) to alleviate the pain caused by rising energy and fuel costs for farmers, households, and businesses.

It cut a sales tax on fertilizers by 46% to 13% and on Thursday announced it would be lowered further, to 6%, and also announced a tax rebate on fuel for agricultural vehicles.

Farmers say the measures do not go far enough and everything has become too expensive, from fuel to animal feed.

“Our survival is really at stake this year,” said one protester, Giorgos Laoutis. “With the cost of production, electricity, agricultural supplies, fuel.”

Farmers from across Greece joined the rally. Some protesters hung black flags on shepherd’s crooks or sticks.

“The situation has become unbearable,” said another farmer, Diamanto Kritikou.

“We can’t work our fields, we can’t cultivate, we can’t put gas in our vehicles, and (we can’t buy) seeds, fertilizers… there will be a problem with food supply in the country,” she said.

Russia’s invasion of Ukraine has driven retail gasoline and diesel prices to record highs.

Russia is also a big producer of potash-, phosphate- and nitrogen-containing fertilizers, and a leader in fertilizer exports, accounting for 13% of world output.

This month, its trade and industry ministry told the country’s fertilizer producers to temporarily halt exports.

As a result of the conflict in Ukraine, the United Nations food agency said last week that international food and feed prices could rise by up to 20%.