UN experts warn Mexico that four LNG terminals and two pipelines in the Gulf of California could clash with climate goals and human rights.
UN human rights experts have put Mexico’s plans for a massive liquefied natural gas build-out in the Gulf of California under formal scrutiny, warning that the country risks trading climate and human rights commitments for a new fossil fuel export boom.
In a letter dated 2 September and made public this week, a group of UN Special Rapporteurs expresses “deep concern” over the legality, climate impact and human rights implications of a cluster of LNG terminals and gas pipelines proposed along the Sonora and Sinaloa coasts. The communication focuses on four export terminals — Terminal GNL de Sonora–Saguaro Energía, Vista Pacífico, AMIGO LNG and GNL Cosalá — and two large pipelines, Sierra Madre and Corredor Norte, that would move US gas to Mexico’s Pacific shore.
The experts say information they received indicates that approvals and reviews have advanced without full, up-to-date environmental impact studies, without clear public access to project data and without effective participation by Indigenous, fishing and rural communities that would live with the consequences. They warn that this combination could put Mexico at odds with its obligations under the Paris Agreement, the Escazú Agreement and its own Constitution.
The letter was triggered by a petition sent in late 2024 by 25 residents and community representatives from the Gulf of California region, supported by Mexican civil society groups. Those signatories argued that the projects would transform the gulf — long known as “the aquarium of the world” — into a sacrifice zone for fossil fuel exports and asked the UN to press both Mexico and the home states of the companies involved for answers.
UN letter raises climate and rights alarms
Mexico has recently stepped up its climate promises. In its latest nationally determined contribution, the country commits to cut greenhouse gas emissions by 35 percent by 2030, with a conditional target of 40 percent if international support materialises. It has also pledged to reach net-zero emissions by 2050 and to adopt an absolute cap on emissions by 2035. Against that backdrop, the experts caution that turning the Gulf of California into a major export corridor for fracked gas sits uneasily with a rapid phase-down of fossil fuels.
According to the communication, the combined output of the four LNG terminals could make Mexico the world’s fourth-largest exporter of liquefied fossil gas. The rapporteurs warn that this would come “at the cost of health, ecosystems, communities and climate goals”, pointing to emissions across the full gas chain, from Permian Basin wells to pipelines, liquefaction plants and tanker traffic. They highlight methane leaks, local air pollution and the risk of locking in high-carbon infrastructure just as global climate science calls for deep cuts this decade.
The letter also frames the dispute as a human rights issue. The experts raise potential impacts on the rights to a clean and healthy environment, to water and food, to health, to culture and to participation in public affairs. Communities along the Sonora and Sinaloa coasts rely heavily on small-scale fishing and coastal tourism. Residents fear that heavy industrialisation and year-round LNG shipping could disrupt fish stocks, harm tourism and deepen existing social inequalities in a region already exposed to heatwaves, hurricanes and drought.
Those concerns are sharpened by the unique status of the Gulf of California. Its islands and protected areas form a UNESCO Natural World Heritage site covering 244 islands, islets and coastal zones. The gulf hosts hundreds of fish species and a remarkable concentration of marine mammals, including endangered whales and the critically endangered vaquita porpoise. Scientific studies and conservation groups have warned that a sharp rise in large tanker traffic could raise the risk of ship strikes on whales, increase underwater noise that interferes with their communication and introduce invasive species through ballast water discharges.
At the same time, LNG plants and associated infrastructure would reshape stretches of coastline that today support small harbours and tourism-based economies. The flagship project, Terminal GNL de Sonora–Saguaro Energía in Puerto Libertad, envisions a large export terminal supplied by the Sierra Madre pipeline, which would bring gas more than 800 kilometres from the US border. Company figures and industry analyses project a capacity in the range of 14–15 million tonnes of LNG per year and regular departures of large tankers bound mainly for Asian markets. Vista Pacífico in Topolobampo and AMIGO LNG in Guaymas would add further export capacity and shipping traffic through the same waters, with GNL Cosalá and the Corredor Norte pipeline extending the footprint inland and along the Sinaloa coast.
UN experts argue that taken together, these projects cannot be treated as isolated investments. They ask Mexican authorities to explain how cumulative impacts on marine ecosystems, fisheries, coastal livelihoods and national emissions have been assessed, and what steps have been taken to ensure free, prior and informed consent where Indigenous peoples are affected. They also pose questions to the governments of the United States and Singapore, as home states of key companies, about their responsibility to prevent cross-border harm.
Gulf of California LNG
Mexico has begun to respond, but without signalling a change of course. The country’s Permanent Mission to the UN has told the experts that the Terminal GNL de Sonora project is currently suspended while at least five amparo lawsuits filed by local communities move through the courts. Environmental authorities have also acknowledged that the project remains under review. Mexico’s president has defended the project as “not irregular” but has said that regulators are still examining gas supply and the need for an additional pipeline.
Those legal battles are part of a wider pushback. Over the past year, coalitions of Mexican organisations have filed complaints, sent urgent alerts to international conservation bodies and lobbied diplomatic missions to halt LNG expansion in the gulf. One coalition, operating under the banner “Ballenas o Gas”, has focused on the risk to whales and dolphins, arguing that an LNG corridor cutting through critical habitat is incompatible with existing protections. Another group of organisations has asked UNESCO, IUCN and the Ramsar Convention to intervene to protect the World Heritage values and wetlands of international importance in the region.
In parallel, an unprecedented lawsuit filed in Mexican courts seeks to recognise whales in the Gulf of California as subjects of rights, with the explicit aim of blocking Saguaro Energía. That case argues that permits granted under a previous administration relied on an outdated environmental impact authorisation issued in 2006 for a different kind of gas terminal and never assessed the cumulative effects of large-scale LNG exports and dense tanker traffic. The suit asks judges to order authorities to revoke those permits and to declare key parts of the gulf critical habitat, which would trigger stronger legal safeguards.
The UN communication lands just weeks after Mexico presented its latest climate plan on the international stage, promising deeper cuts in emissions by 2035 and net zero by mid-century. For critics of the LNG build-out, the timing underscores a contradiction between diplomatic language and domestic energy choices. For the government and companies involved, the letter raises the stakes: any decision to push ahead without stronger studies, transparency and community participation will now unfold under formal international scrutiny.
What happens next will depend on how Mexican authorities answer the UN’s questions and how courts rule on the amparo cases. For now, the Gulf of California sits at the centre of a national argument over what a “just transition” should look like in practice — and whether Gulf of California LNG projects can ever be squared with the country’s promises to protect both its people and one of the most biodiverse seas on the planet.
