In 2020 the Mexican government announced plans to ban imports of GM corn and the use of the herbicide glyphosate in order to protect its native crop biodiversity. Under US pressure – Mexico is a major destination for US corn exports – the government watered down this proposal in February this year, removing the deadline to ban imports of GM corn destined for animal feed.

However, the new presidential decree retains the ban on imports of GM corn destined for human consumption and the use of the herbicide glyphosate.

The US opposes the ban, saying it violates terms of the region’s free trade agreement, the United States–Mexico–Canada Agreement (USMCA). On 6 March, the Office of the United States Trade Representative (USTR) announced it had requested formal trade consultations with Mexico under the sanitary and phytosanitary measures chapter of the trade deal in a bid to derail the decree.

Cofepris and Conacyt: ‘Preserving the integrity of Mexicans’ food’

However, the Mexican government seems intent on standing firm. On 10 April, Mexico’s Federal Commission for the Protection against Sanitary Risks (Cofepris) and the National Council of Science and Technology (Conacyt) announced the formation of a working group that, with the National Reference Laboratory, would work to detect the presence of GM corn in dough and tortillas consumed in the country.

The working group has already begun developing technical and analytical capacities to assess the risks of eating GM corn and the risks of glyphosate use to human health, according to a joint statement by the authorities.

“With [this] taskforce, Cofepris and Conacyt strictly adhere to the presidential decree that protects the health of the population and endorse their commitment to preserving the integrity of the main food source of Mexicans,” read a joint statement in Spanish.

“[...] it is essential that the government of Mexico, through the institutions responsible for scientific and technical analysis, ensure that all transgenic maize materials that enter the country are unviable so that they cannot be used as seeds.”

The Mexican decree on banning GM imports takes the country’s anti-GM stance one step further. In 2013, Mexico prohibited the cultivation of GM and gene-edited corn in Mexico in order to preserve the country’s thousands of native corn varieties and protect biodiversity. This was upheld in 2021 by a Supreme Court ruling.

Speaking to Mexican newspaper DW, Viridiana Lázaro from Greenpeace Mexico said: "Transgenic [GM] maize has affected the diversity of this plant in Mexico." Lázaro added that Mexico had 59 known races of native maize and thousands of variants that are being continually diversified. Because corn reproduces through open pollination, pollen from GM plants can fertilise other plants and contaminate native and landrace seeds.

US farmers call for elimination of future trade barrier

The US farming and biotech industry welcomed the news that the US trade office was seeking technical consultations with Mexico on the GM ban.

Ryan LeGrand, president and CEO of the US Grains Council, said the US has had a long and productive relationship with Mexico, which was the number one market for US corn. “We support this action because it will likely be the most expedient way to ensure that positive relationship continues,” he added.

Tom Haag, president of the US National Corn Growers Association, said: “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.

“Mexico’s position on biotech corn is already creating uncertainty, so we need US officials to move swiftly and do everything it takes to eliminate this trade barrier in the very near future.”

The Biotechnology Innovation Organization said it was time to “send a strong message to the government of Mexico and return to the science-based trading system and obligations to which both our countries committed when we signed the US-Mexico-Canada Agreement”.