Mexico has until October 2025 to make good on a treaty requiring them to deliver water to the United States.

"Mexico, under that treaty, is supposed to be releasing 350,000 acre feet every year. So far, on this five-year cycle, which it ends next year, the only thing they've done is they've only delivered 400,000 out of 1.2 million acre feet that they should have delivered," Congressman Henry Cuellar said.

RELATED COVERAGE: Water levels at Falcon Reservoir reaching historic lows

Lawmakers in D.C. are getting closer to withholding funding for Mexico until those water deliveries are secured.

A bipartisan group of Texas lawmakers secured language in the next fiscal year's State, Foreign Operations, and Related Programs appropriations bill.

The appropriations bill now heads to the full house chamber for consideration.

Water levels at Rio Grande Valley reservoirs are at historic lows and has caused water restrictions and calls for conservation.