CANCUN, Mexico— Conservation groups have sued the Mexican government over its plan to build a “Maya train” through one of Mexico’s most biodiverse forests. This controversial tourist train — one of President López Obrador’s flagship infrastructure projects — will connect holiday destinations across the Yucatán peninsula. The lawsuit challenges the government’s failure to issue an environmental assessment before approving the train’s fifth and most-controversial section.

In November 2021 President López Obrador published a decree unilaterally waiving all permitting requirements for several of his priority infrastructure projects, including the Maya train.

The suit, filed Tuesday in the 3rd District Court of the state of Quintana Roo, challenges the waiver and the most damaging section of the train that connects south Cancun to Tulum, punching a thick, 75-mile line through key habitat for imperiled blindfish, imperiled cats and monkeys and underwater caves and rivers.

“This Maya train construction is already harming the habitat of jaguars, ocelots, Yucatan spider monkeys and many other imperiled animals,” said Alex Olivera, senior scientist and Mexico representative at the Center for Biological Diversity. “President López Obrador must halt construction until his agencies actually follow the law and assess the train’s threat to this beautiful, biodiverse forest.”

The conservation groups’ suit also challenges the authorization for building the elevated train issued illegally by Mexico’s environmental agency, Semarnat. Initial plans for the train’s route changed and now the train will traverse underwater caves and devastate kilometers of forests. The Mexican government violated the Regional Agreement on Access to Information, Public Participation and Justice in Environmental Matters, also known as the Escazú Agreement, by issuing the permit and denying access to environmental information and public participation in environmental decision-making.

“Through this lawsuit, we call on the authorities to comply with and enforce the constitution,” said Aleira Lara, campaigns director for Greenpeace Mexico. “The way this project has been authorized violates the right to public participation, the right to have environmental impact information, and the right to sustainable development, and it leaves the precautionary principle without effect. Deforestation and other activities that have been carried out to this day are completely illegal, and no promise of mitigation or subsequent repair can serve as a guarantee for a path that is not authorized.”

If the suit is admitted in the Yucatan court, a suspension of the construction project could be granted in the following days.