On December 8, 2025, Donald Trump used his Truth Social account to threaten **tariffs and possible sanctions on Mexico** over what he called violations of the **1944 U.S.–Mexico Water Treaty** governing shared use of the Rio Grande, Colorado, and Tijuana rivers. He asserted that Mexico owed the United States about **800,000 acre-feet of water**, demanded the release of **200,000 acre-feet by the end of the year**, and warned that a **5% tariff on Mexican imports** would be imposed or expanded if Mexico did not comply, arguing that the shortfall was harming Texas farmers and ranchers. The dispute centers on Mexico’s obligation under the treaty to deliver an average of **350,000 acre-feet per year, or 1.75 million acre-feet over each five‑year cycle**, via six Mexican tributaries flowing into the Rio Grande, in exchange for U.S. deliveries of Colorado River water to Mexico. The threat escalated a long‑running bilateral conflict over Mexico’s repeated failure, since the 1990s, to consistently meet its five‑year water delivery commitments, a problem exacerbated by drought, rising temperatures, and growing agricultural and urban water demand on both sides of the border. Trump’s message framed the issue as Mexico “stealing” or withholding water owed to **Texas producers in the Rio Grande Valley**, and linked trade measures directly to treaty compliance, signaling a willingness to use economic pressure tools typically reserved for broader trade or security disputes. Within days, the U.S. Department of Agriculture announced that the United States and Mexico had reached an understanding under which Mexico would release about **202,000 acre‑feet of water** starting mid‑December 2025 and work to repay the outstanding deficit from the previous cycle, a move that allowed Mexico to begin deliveries and avoid the immediate imposition of the 5% tariff but left open the threat of future trade measures if it again fell behind on its treaty obligations.

✨ AI-generated background, compiled from web sources — not editorial content.

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