Tech billionaire Elon Musk offered to produce ventilators in the event of a shortage during the coronavirus outbreak.

“We will make ventilators if there is a shortage,” Musk, the founder to Tesla, said on Twitter late Wednesday night.

We will make ventilators if there is a shortage

— Elon Musk (@elonmusk) March 19, 2020

Musk went on to indicate that he would direct that ventilators be sent to hospitals acutely affected by a potential shortage but that production would take time.

“Tesla makes cars with sophisticated hvac systems. SpaceX makes spacecraft with life support systems. Ventilators are not difficult, but cannot be produced instantly. Which hospitals have these shortages you speak of right now?” he tweeted in response to a question from FiveThirtyEight’s Nate Silver.

Tesla makes cars with sophisticated hvac systems. SpaceX makes spacecraft with life support systems. Ventilators are not difficult, but cannot be produced instantly. Which hospitals have these shortages you speak of right now?

— Elon Musk (@elonmusk) March 19, 2020

The offer marks a reversal for Musk, who said last week the “panic” fueled by the coronavirus was “dumb.”

Musk’s remarks come as state officials already face the threat of a shortage of masks and ventilators as hospitals burn through their stockpiles of masks, called N95 respirators, for health workers.

Hospitals in the United States have about 162,000 ventilators in addition to another 12,700 in a reserve of emergency medical supplies overseen by the federal government, The New York Times reported Wednesday. However, it is unclear if that cache will be sufficient if the number of cases continues to rise.

President Trump on Wednesday said he will invoke the Defense Production Act to allow the administration to force American industry to manufacture medical supplies that are in short supply.

White House economic adviser Larry Kudlow also said Wednesday that General Motors CEO Mary Barra offered to use the company’s factories to produce ventilators. The Pentagon will also give the Department of Health and Human Services 5 million respirator masks and up to 2,000 deployable ventilators to bolster its stockpile.