MEXICO CITY, Mexico (CNN) -- Hundreds of thousands of farmers clogged central Mexico City Thursday with their slow-moving tractors, protesting the entry of cheap imported corn from the United States and Canada.
On January 1 Mexico repealed all tariffs on corn imported from north of the border as part of a 14-year phaseout under the North American Free Trade Agreement, or NAFTA.
The farmers want the government to renegotiate the 1994 free trade agreement, which removed most trade barriers among Mexico, Canada, and the United States, saying livelihoods are at stake.
"NAFTA is very bad, very bad for Mexican consumers and for Mexican producers," said Victor Quintana, head of Democratic Farmers Front, which organized the protest.
The farmers complain that U.S. and Canadian grains are heavily subsidized and therefore undermine Mexican products.
"The NAFTA agreement is in place and that's that," said farmer Armando del Valle. "But all producers should be under equal conditions, and as Mexicans, we are not working under the same terms as our neighbors up north." Watch a tractor go up in smoke, as farmers plead their case »
Ramon Garcia, who grows corn just outside Mexico City, said he couldn't afford to fertilize his crop this year and had to rent a tractor to till his field. The work is too much work for too little return, he said.
"Corn is too cheap," Garcia said. "For me to make a profit, it has to bring in 15 pesos ($1.4) a kilo, and I can barely get 10."
The farmers say their pleas have fallen on deaf ears in the Mexican government, forcing them to take their protests to the streets.
The government has said NAFTA is working fine and won't be renegotiated but promised to negotiate with farmers to find ways to increase their subsidies.
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