REYNOSA, TAMAULIPAS – Overcrowded migrant shelters across the border are bracing for changes part of Mexico's bi-national agreement to reduce migration into the U.S.

The country agreed to expand a program that sends migrants back to Mexico while they await U.S. immigration proceedings.

State-run shelters in Tamaulipas are concerned about the changes, but are looking forward to newly announced aid.

Shelters have faced crowded conditions since the implementation of the Zero Tolerance Policy a year ago.

The policy kept migrants on the Mexican side of bridges waiting their turn to claim asylum in the U.S.

Thousands huddled into shelters, many of them operated by the state of Tamaulipas.

Jose Carmona Flores, federal director of the Tamaulipas Migrant Institute, admits, "Our houses offering migrant help, the shelters are completely full; they're over-capacity."

Crowded conditions and tightly regulated borders led many migrants to circumvent ports of entry and request asylum after arriving on U.S. territory. 

Those crowds could find themselves back in state shelters, but for greater periods of time.

The Migrant Protection Protocols, or MPP, was created to address that kind of immigration.

Under the policy, many migrants will be sent back to wait out their U.S. immigration proceedings in Mexico. 

The program will be expanded across the entire Southwest border, according to the announcement made June 7. It went into effect at three ports of entry last year. 

Tamaulipas state-run shelters already house thousands of migrants waiting to cross and Mexican nationals recently deported.

Flores says they've already received about 26,000 deported Mexican nationals; last year, they received about 59,000 in the state.

The shelters would experience some relief when the migrants crossed into the U.S., but that is subject to change under MPP.

Flores says, "We had hoped that slowly they were going to start leaving because they intended to cross into the U.S., but now we're learning they're going to be waiting on the Mexican side."

Federal funding to border states was severely impacted in the current budget.

Monday, the federal government announced their plans to help. 

Flores says, "The shelters will receive federal help directly, and the federal government will through their National Institute of Migration will be in charge of new shelters."

Mexico's president announced Monday they plan to create federally-operated shelters.

For now, Tamaulipas will have new federal partners to troubleshoot how they will provide assistance for the migrants who will need long-term arrangements under MPP.  

Flores says, "Now we're going to start having meetings with the (MX) Department of Labor, the (MX) Department of the Public Region, and a few others departments of social wellness. The migrants are going to enter the labor force, the productive life of the country, and we don't want employers to feel uncertain about hiring them if they don't have documents."

The shelters are temporary, but the waiting under MPP can take over a year.

Tamaulipas and other border states will be tasked to create a system that can provide housing, employment and educational opportunities to migrant families sent back to Mexico under the policy. 

As of now, Flores reports the state of Tamaulipas has not received back any migrants under the Migrant Protection Protocols.

U.S. authorities did not specify when it would start in the Rio Grande Valley. 

Mexico's agreement signed to ward off tariffs established a 45-day deadline to reduce migration numbers.