Trump Warns of Fresh 5% Tariff on Mexico Over Alleged Water Treaty Breach

Story: written by Joseph December 9,2025
President Donald Trump on Monday issued a fresh warning to Mexico, saying his administration is ready to impose an additional 5% tariff if the country does not immediately fulfil its water-sharing obligations to the United States.

Posting on his Truth Social account, Trump said he had authorised all necessary documents to trigger the tariff should Mexico fail to comply, insisting that farmers and ranchers in Texas are already facing significant hardship.

He accused Mexico of violating the 1944 Water Treaty, which mandates that both nations deliver agreed-upon water supplies from the Colorado River and the Rio Grande—part of the natural border between the two countries.

According to Trump, Mexico currently owes the U.S. 800,000 acre-feet of water under the treaty. He demanded that 200,000 acre-feet be released before December 31, with the rest to follow soon after.

“The longer Mexico delays, the more harm is inflicted on our farmers,” Trump wrote.

The threat was issued the same day the president rolled out a $12 billion support package for American agriculture, a sector still reeling from broader trade tensions and previous tariff measures.

This is not the first time Trump has confronted Mexico on the issue. In April, he delivered a similar ultimatum, prompting Mexico to release water and reaffirm its commitment to the treaty.