(Bloomberg) -- The Biden administration plans to escalate its conflict with Mexico over the Latin American nation’s restrictions on genetically modified US corn and other agricultural products with a request for formal consultations under their free-trade agreement.

The decision comes after the US repeatedly conveyed to Mexico serious concerns about the country’s biotechnology policies that threaten to disrupt billion of dollars in agricultural trade, US Trade Representative Katherine Tai said in a statement.

The Mexican government has moved to limit imports and use of US GMO corn, saying that it could pose a danger to the health of the nation’s citizens. The US counters that Mexico’s concerns aren’t based in science.

Mexico’s policies “will stifle the innovation that is necessary to tackle the climate crisis and food security challenges if left unaddressed,” Tai said. “We hope these consultations will be productive as we continue to work with Mexico to address these issues.”  

Mexico’s Economy Ministry said it had received the USTR’s request to start the consultation process. 

The ministry will “demonstrate with data and evidence that there has not been an effect on trade” and that Mexico has acted in accordance with the US-Mexico-Canada agreement. The ministry also said it doesn’t see the US request as “contentious,” but rather as a preliminary step toward finding “a solution in a cooperative manner.”

US Agriculture Secretary Tom Vilsack said he was hopeful that Washington’s concerns can be fully addressed. 

“Absent that, we will continue to pursue all necessary steps to enforce our rights under the USMCA to ensure that US producers and exporters have full and fair access to the Mexican market,” he said in a statement.

The consultations under the USMCA’s chapter on food-safety measures are a pre-requisite for formal dispute resolution talks, like those that the US and Mexico have already had on automobiles and energy. Those dispute talks could be requested if the technical discussions don’t take place or don’t lead to a resolution. 

US officials have spoken with their Mexican counterparts for more than a year in a push to resolve the issue, including a virtual meeting at the end of February between Tai and Mexican Economy Minister Raquel Buenrostro.

After that meeting, Mexico said that the US’s disagreement with its decree regulating GMO corn “lacks trade fundamentals” and has a political motivation. The USTR responded that the concerns aren’t politically motivated. Mexico’s policies threaten to disrupt billions of dollars in agricultural trade, causing serious economic harm to US farmers and Mexican livestock producers, a USTR spokesman said. They could also stifle innovation that’s needed to respond to urgent climate and food security challenges.

The US National Corn Growers Association welcomed the USTR’s move.

“We are pleased USTR is taking the next step to hold Mexican officials accountable for the commitments they made under USMCA, which include accepting both biotech and non-biotech commodities,” said President Tom Haag. “Mexico’s position on biotech corn is already creating uncertainty, so we need U.S officials to move swiftly and do everything it takes to eliminate this trade barrier in the very near future.”

Vilsack last month rebuffed a concession by Mexico in the simmering trade dispute, saying he was “disappointed” by Mexican President Andres Manuel Lopez Obrador’s decree that would press forward with a prohibition on GMO corn for human consumption, while scrapping a deadline to halt imports of GMO corn for livestock feed.

The Mexican government’s efforts to block imports of US GMO corn have become one of the biggest trade irritants between Mexico and its northern neighbor. Mexico is the US’s second-largest export market and the issue has mobilized President Joe Biden’s administration, as well as elected representatives in key corn-growing states including Iowa Senators Chuck Grassley and Joni Ernst. 

Mexico last month announced plans to eliminate a previous deadline to ban GMO corn for animals and manufactured products, with the phase-out instead depending on supply and establishing working groups with domestic and foreign businesses for an orderly transition. But Mexico will still prohibit the importation of GMO corn for flour and tortillas, as well as glyphosate, a commonly used pesticide.

--With assistance from Maya Averbuch and Dale Quinn.

(Updates with comment from Mexican economy ministry in fifth paragraph.)

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