As the U.S. nears 60,000 deaths from the coronavirus, President Donald Trump has signed an executive order declaring meat processing plants "critical infrastructure" to try to keep them open and stave off shortages.

Closures of meat processing plants following outbreaks of the virus "threaten the continued functioning of the national meat and poultry supply chain, undermining critical infrastructure during the national emergency," Trump said in the Tuesday order, which invokes the Defense Production Act.

Twenty-two processing plants have closed in the past two months, reducing pork processing capacity by 25% and beef processing capacity by 10%, according to the United Food and Commercial Workers International Union.

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On Tuesday, the U.S. topped 1 million cases of the coronavirus. The country reports nearly a third of all global cases.

Trump commented on the development, saying other countries show fewer cases because they aren't doing as many tests.

"The only reason the U.S. has reported one million cases of CoronaVirus is that our Testing is sooo much better than any other country in the World," Trump tweeted. "Other countries are way behind us in Testing, and therefore show far fewer cases!"

Anthony Fauci, a member of the White House coronavirus task force, said on Tuesday that it is "inevitable" the virus will have a second wave. He warned that the severity of the outbreak depends on how the U.S. prepares for it.

"If by that time we have put into place all of the countermeasures that you need to address this, we should do reasonably well," Fauci said. "If we don't do that successfully, we could be in for a bad fall and a bad winter."

The task force didn't hold a briefing on Tuesday. The administration is reportedly scaling back the marathon press conferences.