Mexico’s bold move this week to reinforce its drive to disparage genetically modified corn and ban imports ignores protests from the Biden administration, adding pressure on the U.S. to follow through with recent threats to initiate a dispute under the U.S.-Mexico-Canada Agreement.

“We’re not happy,” said National Corn Growers Association President Tom Haag in response to the decision of Mexican President Andrés Manuel López Obrador to publish a new decree Tuesday that promises to ban the import of GM white corn immediately and eventually block imports of yellow corn for feed and industrial uses after Mexico can replace what it buys from the U.S.

The new decree, which replaces a more ambiguous 2020 version that appeared to flat-out ban all GM corn by Jan. 31, 2024, is already being criticized by the Biden administration and industry officials who say they are hoping it will spur the Office of the U.S. Trade Representative to challenge Mexico under USMCA.

“Upon initial review, USDA is disappointed in Mexico’s new decree regarding genetically modified corn,” Agriculture Secretary Tom Vilsack said in a statement provided to Agri-Pulse. “The U.S. believes in and adheres to a science-based, rules-based trading system and remains committed to preventing disruptions to bilateral agricultural trade and economic harm to U.S. and Mexican producers.

“We are carefully reviewing the details of the new decree and intend to work with USTR to ensure our science-based, rules-based commitment remains firm,” Vilsack added.

A U.S. trade official says the Office of the USTR is still reviewing it before commenting publicly.

The latest decree, which bans GM white corn immediately, is similar to the proposal the López Obrador administration presented to Washington in December, which was flatly rejected by the Biden administration.

The U.S. exported 15.4 million metric tons of corn to Mexico in 2022 — about 1.6 million of which is white corn —  according to USDA data. Almost all of it was grown from genetically engineered seeds.

NCGA was clear Tuesday in its disappointment with the decree.

Tom HaagTom Haag, NCGA

“The Biden administration has been more than patient with Mexico as U.S. officials have sought to enforce a rules-based trading system and stand up for American farmers,” said Haag. “The integrity of USMCA, signed by Mexican President Andrés Manuel López Obrador himself, is at stake. Singling out corn — our number one ag export to Mexico — and hastening an import ban on numerous food-grade uses makes USMCA a dead letter unless it’s enforced.” 

Haag said NCGA intends to keep up its monthslong pressure campaign on the Biden administration to challenge Mexico’s anti-biotech policies.

But the Office of the USTR still has not yet begun the lengthy process of challenging the first decree under USMCA, although it has begun the groundwork.

Calls from U.S. lawmakers and farm groups for the Office of the USTR to challenge Mexico on its efforts to ban GM corn have been getting louder, and López Obrador's doubling down on a path that could cost the U.S. billions of dollars in export losses is exacerbating the situation.

Several senators used a Feb. 1 Agriculture Committee hearing to press Alexis Taylor, USDA undersecretary for trade and foreign agricultural affairs, on the need to fight Mexico.

One of those senators, Republican Chuck Grassley of Iowa, told Agri-Pulse he was only willing to wait 30 days for the Biden administration to file a trade dispute with Mexico, but a review of the USMCA process shows that’s not possible. If the U.S. started the process now, it could take at least six months just to get to the point where a third-party dispute panel could be requested under USMCA.

The first step the U.S. would have to take is to request technical consultations with Mexico under USMCA’s Chapter on Sanitary and Phytosanitary Measures. Once that happened, the two sides would have 30 days to begin meeting and 180 days to try to resolve their differences. If that fails, dispute consultations may be called for, and after that, a third-party dispute panel can be requested to act as a judge in the matter.

All told, it can take at least 210 days from the dispute panel request until a final judgment is reached.

But the USTR is still preparing for the first set of technical consultations.

USTR Chief Agricultural Negotiator Doug McKalip and Deputy USTR Jayme White sent a letter on Jan. 30 to Mexican Undersecretary of Foreign Trade Alejandro Encinas Najera, asking for scientific justifications behind the original 2020 decree.

USTR and USDA officials have been consistent in criticism that Mexico’s efforts to ban GM corn are not based on science, and the USTR letter seeks to get Mexico on the record for its reasoning.

“These measures do not appear to be based on a relevant standard, guideline or recommendation,” the letter states before demanding proof of any such standards that back up Mexico’s claim that genetically engineered corn presents health threats.

McKalip and White said in the letter they wanted answers to all of their questions by Feb. 14; Mexico still has not responded.

A U.S. trade official who asked not to be named stressed that Mexico’s issuance of a new decree does not relinquish it from answering the questions USTR submitted on the original 2020 decree.

The official said USTR still expects “Mexico to submit written responses” to the questions and added that the “revised decree is not a substitute for a formal response.”

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