Washington – President Donald Trump took executive action to order meat processing plants to stay open amid concerns over growing coronavirus cases and the impact on the nation’s food supply.

The order signed Tuesday uses the Defense Production Act to classify meat processing as critical infrastructure to try to prevent a shortage of chicken, pork and other meat on supermarket shelves. Unions fired back, saying the White House was jeopardizing lives and prioritizing cold cuts over workers’ health.

More than 20 meatpacking plants have closed temporarily under pressure from local authorities and their own workers because of the virus, including two of the nation’s largest, one in Iowa and one in South Dakota. Others have slowed production as workers have fallen ill or stayed home to avoid getting sick.

“Such closures threaten the continued functioning of the national meat and poultry supply chain, undermining critical infrastructure during the national emergency,” the order states.

The United Food and Commercial Workers International Union, which represents 1.3 million food and retail workers, said that 20 food-processing and meatpacking union workers in the U.S. have died of the virus as of Tuesday. An estimated 6,500 are sick or have been exposed while working near someone who tested positive, the union says.

As a result, industry leaders have warned that consumers could see meat shortages in a matter of days. Tyson Foods Inc., one of the world’s largest food companies, ran a full-page advertisement in The New York Times warning, “The food supply chain is breaking.”

“As pork, beef and chicken plants are being forced to close, even for short periods of time, millions of pounds of meat will disappear from the supply chain,” the advertisement read.

Tyson suspended operations at its pork plant in Waterloo, Iowa after a slew of infections, and Smithfield Foods halted production at its plant in Sioux Falls, South Dakota, after an outbreak.

The 15 largest pork-packing plants account for 60% of all pork processed in the U.S., and the country has already seen a 25% reduction in pork slaughter capacity, according to UFCW.

A senior White House official said the administration was trying to prevent a situation in which a “vast majority” of the nation’s meat processing plants might have temporarily closed operations, reducing the availability of meat in supermarkets by as much as 80%.

The order, which was developed in consultation with industry leaders including Tyson and Smithfield, is designed, in part, to provide companies with additional liability protections in case workers get sick.

Trump on said the order would address what he described as a “legal roadblock.” It will “solve any liability problems where they had certain liability problems and we’ll be in very good shape.”

But UFCW International President Marc Perrone said that more must be done to protect the safety of workers.

“Simply put, we cannot have a secure food supply without the safety of these workers,” he said.

Stuart Appelbaum, president of the Retail, Wholesale and Department Store Union, said the administration should have acted earlier to put safety measures in place.

“We only wish that this administration cared as much about the lives of working people as it does about meat, pork and poultry products,” he said.

The administration is working with companies to help them secure protective equipment, like face shields and masks, and ramp up testing, an official said. The Centers for Disease Control and Prevention and the Occupational Safety and Health Administration have issued extensive guidelines on steps companies and workers should take.

When outbreaks have happened, local public health agencies have pushed in some cases for temporary closures so they can limit wider outbreaks in communities and conduct mass testing to determine who is carrying the virus. Some plants have also briefly closed for deep cleaning and to install new safety measures. Yet concerns about working conditions persist and have led some to walk off the job.