The Trump administration has ordered contractors to stop drilling new wells for border wall construction in drought-stricken New Mexico after ranchers warned the project could drain groundwater needed to keep their livestock alive.

The decision follows complaints that contractors were pumping or preparing to pump large volumes of groundwater to supply concrete production for President Donald Trump's expanded border wall project, which has received more than $46 billion in federal funding.

U.S. Customs and Border Protection confirmed Monday that contractors have been instructed to halt drilling new wells in New Mexico while the agency works with state officials and the U.S. Department of Agriculture on a long-term groundwater strategy.

"CBP is committed to working collaboratively with local landowners to ensure that construction activities do not adversely impact their water needs," the agency said.

The agency did not say whether wells that have already been drilled will be allowed to pump water.

The move comes after ranchers raised alarm over the scale of the proposed water extraction during one of the state's worst droughts.

Russell Johnson, whose ranch borders the construction zone, said he discovered an industrial well on grazing land he leases after construction crews told him it could pump up to 300 gallons of water per minute.

By comparison, Johnson said the 12 wells on his ranch each produce between three and seven gallons per minute.

"It would put us in an immediate catastrophe and having to do something with our livestock," Johnson said. "It could potentially put some people out of business, us included."

The New Mexico Office of the State Engineer said investigators have identified eight wells drilled along the southern border without state approval and warned additional unauthorized wells could exist.

Officials who inspected two of the wells in July found they were pumping about 200 gallons per minute.

State officials said all non-tribal wells in New Mexico require permits before drilling or pumping water, regardless of whether they are located on state or federal land.

The wells were drilled on the federally owned Roosevelt Reservation, a strip of land running along the U.S.-Mexico border. CBP did not respond to questions about whether it believes federal authority overrides state groundwater permitting requirements.

Tom Patterson, president of the New Mexico Cattle Growers' Association, said ranchers support securing the border but fear losing access to the water they depend on to survive.

During Trump's first term, he said border wall contractors purchased water from nearby farms, ranches and local governments instead of drilling new wells.

"Why do they need all this water? And why can't they buy it as they have in the past from farmers, ranchers, or even from Luna County?" Patterson said.

Johnson said the pause on new well drilling is welcome but remains concerned that contractors could eventually begin pumping from existing wells if construction demands increase.

The prolonged drought has already forced him to cut his cattle herd to about one-third of its previous size because of shrinking grazing land.

A former Border Patrol agent, Johnson said he supports the construction of the border wall but believes it should not come at the expense of local ranchers.

"They need to stop pumping all of these wells because they were all drilled illegally," he said.

The dispute has also become a political flashpoint ahead of November's midterm elections.

Republican congressional candidate Greg Cunningham said he pushed the Trump administration to pause the drilling after hearing concerns from ranchers.

Democratic Rep. Gabe Vasquez also claimed credit, saying he pressed federal officials to protect New Mexico's water rights after learning of the unauthorized wells.