Rio Grande Valley police departments no longer will have direct access to their counterparts on the south side of the border.
The Mexican government said it will limit the information it shares with U.S. law enforcement agencies.
Mexican President Enrique Pena Nieto's administration said all information will be disseminated through the ministry of interior in Mexico City.
The announcement is a 180-degree turn from the open dialogue both nations had on law enforcement.
The change likely will delay investigations Valley lawmen said.
"It'll still trickle down to us. It might be a little slower, but we'll still get the information we need," Rio Grande City Assistant Police Chief Noe Castillo said.
Castillo said they will utilize community resources to get the information they need.
A businessman who runs a produce company in Hidalgo and Reynosa said the change is troublesome.
He said the situation along the border is bad enough now, and could get worse with the change. He said it may force him to go out of business.Meanwhile, while Richard Milhous Obama headed to Mexico today, this topic wasn't on his agenda.