Donald Trump has issued a warning to Mexico, threatening additional tariffs due to their persistent breach of a water agreement that has been in place for nearly 100 years.

The former president’s demand comes as he shifts attention back to American agriculture, highlighting a $12 billion relief package on his Truth Social platform Monday evening.

“Mexico continues to breach our long-standing Water Treaty, causing significant harm to our BEAUTIFUL TEXAS CROPS AND LIVESTOCK,” Trump stated.

He further explained that Mexico “still owes the US over 800,000 acre-feet of water for non-compliance with our Treaty over the past five years. The US needs Mexico to deliver 200,000 acre-feet of water before December 31st, with the remainder required shortly after.”

Despite praising Mexican President Claudia Sheinbaum at the World Cup draw event in Washington on Friday, Trump noted he has yet to receive any response from Mexico.

‘It is very unfair to our US Farmers who deserve this much needed water. That is why I have authorized documentation to impose a 5 percent Tariff on Mexico if this water isn’t released, IMMEDIATELY. The longer Mexico takes to release the water, the more our Farmers are hurt. Mexico has an obligation to FIX THIS NOW.’

The president, who has had an up and down relationship with Mexico throughout his second term, previously made this threat in April.

Under the treaty, Mexico must send 1.75 million acre-feet of water to the US from the Rio Grande through a network of interconnected dams and reservoirs every five years. 

Donald Trump threatened Mexico with an additional tariff over their continued violation of a nearly century-old water treaty

An acre-foot of water is enough to fill about half an Olympic-sized swimming pool. 

Mexican officials have routinely pointed to a historic drought fueled by climate change as a barrier to fulfilling water commitments, a scenario for which the treaty offers leniency, allowing the water debt to be rolled over to the next five-year cycle.

The treaty also requires that the US deliver 1.5 million acre-feet of water annually to Mexico from the Colorado River, an obligation that the US has largely fulfilled, although recent deliveries have been reduced due to severe drought, something the 1944 accord allows for.

The most recent five-year cycle ended in October, with reports Mexico has sent less than 30 percent of the required water, according to data from the International Boundary and Water Commission. 

Mexican President Claudia Sheinbaum, in response, said on X that Mexico has been complying with the treaty ‘to the extent water is available’ amid three years of drought.

She sent a proposal to US officials on Wednesday, Sheinbaum said, to address the water supply to Texas, which includes short-term actions. 

Sheinbaum said she instructed her environment, agriculture and foreign ministers to immediately contact US officials.

‘I am sure, as on other issues, an agreement will be reached,’ Sheinbaum said.

Mexican officials have routinely pointed to a historic drought fueled by climate change as a barrier to fulfilling water commitments, a scenario for which the treaty offers leniency, allowing the water debt to be rolled over to the next five-year cycle 

Trump, who lavished praise on Mexican President Claudia Sheinbaum at the World Cup draw in Washington Friday, said that he has gotten no response yet

While Mexico sends far less water to the US, it has struggled to fulfill its end of the bargain due to a combination of factors including droughts, poor infrastructure and growing local demand.

Politicians in the US also maintain that Mexico’s growing cattle and pecan industries along the border have used up precious water, and they say Mexico’s failure to deliver its water quota devastates Texan farmers who need it for their crops.

Reuters, citing sources, reported on Wednesday that Mexican officials were scrambling to come up with a plan to increase the amount of water sent to the United States because of growing concern that Trump could drag the dispute into trade negotiations.

Texas Republicans have publicly accused Mexico of being chronically delinquent in its water deliveries and flagrantly ignoring the treaty.

In an attempt to increase deliveries, Mexico has agreed to send 122,000 acre-feet of water to the US and is working on an option to deliver another 81,000 acre-feet, a Mexican official told Reuters.

But that would still mean Mexico had sent less than 40 percent of the water it owes under the treaty.

Trump said in April that Senator Ted Cruz ‘has been leading the fight’ to get Texas farmers their water but ‘Sleepy Joe’ Biden ‘refused to lift a finger’.

The president reiterated his demand after a day spent announcing a $12 billion taxpayer lifeline for the battered farm belt on Monday as soaring prices trigger panic inside the White House. 

The president reiterated his demand after a day spent announcing a $12 billion taxpayer lifeline for the battered farm belt on Monday as soaring prices trigger panic inside the White House 

Donald Trump and Treasury Secretary Scott Bessent listen as National Economic Council Director Kevin Hassett speaks, at the White House in Washington, DC, September 5

The president will unveil the plan at a roundtable with Treasury Secretary Scott Bessent, Agriculture Secretary Brooke Rollins, lawmakers and farmers.

Farmers in deep-red states have backed Trump politically but now face disastrous losses from his trade wars – particularly with China, the top buyer of American soybeans. 

Trump slashed Beijing’s soybean imports to zero earlier this year until cutting a deal in October. China imports 29 million metric tons of the beans – the world’s biggest buyer – to feed its huge pork industry.

With grocery prices crushing families and farm incomes in free-fall, the GOP privately fears 2026 will replay the economic backlash that buried Joe Biden in 2024 – unless Trump delivers fast relief to the farm belt. 

Amid White House panic over soaring prices, Treasury Secretary Scott Bessent admitted Chinese tactics left soybean farmers hung out to dry during the stalled negotiations.

‘These prices haven’t come in, because the Chinese actually used our soybean farmers as pawns in the trade negotiations,’ he told CBS’s Face the Nation on Sunday.

The White House says the aid is meant to help farmers who have suffered from trade wars with other nations, inflation, and other ‘market disruptions’.