Mexico’s top diplomat said Friday her country has sent a diplomatic note to the U.S. government expressing concern that Texas’ deployment of floating barriers on the Rio Grande may violate 1944 and 1970 treaties on boundaries and water.

Foreign Relations Secretary Alicia Bárcena said Mexico will send an inspection team to the Rio Grande to see whether any of the barrier extends into Mexico’s side of the border river.

She also complained about U.S. efforts to put up barbed wire on a low-lying island in the river near Eagle Pass, Texas.

Bárcena said that if the buoys impede the flow of water, it would violate the treaties, which requires the river remain unobstructed. Mexico has already asked that the barriers be removed.