Trump Threatens 5% Tariff on Mexican Imports If Mexico Fails to Deliver Water Under 1944 Treaty

Tensions between the United States and Mexico have escalated after U.S. President Donald Trump threatened a 5% tariff on Mexican imports.

“Mexican President Claudia Sheinbaum speaks at her first state-of-the-nation address at the National Palace in Mexico City, Sept”

Associated Press

He said the tariff would be imposed unless Mexico delivers additional water under the 1944 treaty that governs Rio Grande/Bravo allocations.

Associated Press

The treaty requires Mexico to deliver roughly 1.75 million acre‑feet over five years, about 350,000 acre‑feet per year.

The U.S. Section of the International Boundary and Water Commission (IBWC) reported that Mexico had delivered 884,861 acre‑feet as of the cycle’s final accounting date, about 50.6% of the required volume.

Trump’s public pressure included a Truth Social post on Dec. 9, 2025 asserting Mexico "still owed more than 800,000 acre‑feet" and demanding 200,000 acre‑feet be released before Dec. 31, warning of tariffs if it is not.

Mexican officials cite historic drought, storage constraints and physical limits in the Rio Grande basin—conditions the treaty anticipates—as explanations for the shortfall.

The U.S. government’s factual anchor for the dispute is the IBWC's accounting of deliveries, and Mexico Business News reproduces that IBWC figure while presenting Mexican officials' explanation that drought and physical constraints—conditions contemplated by the 1944 treaty—account for the deficit.

The Associated Press cites the same drought and pipeline limitations as causes for missed deliveries but emphasizes the political angle, noting Trump's tariff threat and his claim that the accumulated 'water debt' harms Texas farmers.

Mexico Business News

AP also reports that Mexico, through President Claudia Sheinbaum, intends to propose a phased delivery schedule to be discussed virtually with U.S. officials.

On the U.S. side, reporting shows the administration is using both factual accounting and public pressure.

“Mexican President Claudia Sheinbaum speaks at her first state-of-the-nation address at the National Palace in Mexico City, Sept”

Associated Press

Mexico Business News cites the IBWC total and Trump's Truth Social demand for a near-term release, while the Associated Press frames the administration's posture as a tariff ultimatum tied to agricultural harm in Texas.

Neither source reports that a formal U.S. tariff has already been imposed.

Both describe a threat of a 5% tariff if deliveries are not made and note Mexico's response that it plans to send additional water but not instantly.

Key uncertainties remain about the precise schedule and volume Mexico will commit to in virtual talks.

It is unclear whether the U.S. will move from threats to actual tariffs.

Mexico Business News

Another uncertainty is how IBWC accounting will be applied to disputed causes such as drought versus noncompliance.

The two sources together provide a consistent core of facts: treaty obligations, IBWC delivery totals, Trump's public statements, and Mexico's cited constraints.

They diverge in emphasis, with Mexico Business News foregrounding technical, defensive Mexican explanations and Associated Press emphasizing the political and agricultural impacts highlighted by the U.S. administration.