The president says lifting mask mandates and easing restrictions is a big mistake.
"I hope everybody's realized by now these masks make a difference. We are on the cusp of being able to fundamentally change the nature of this disease because of the way in which we were able to get vaccines in people's arms," he said. "The last thing we need is the Neanderthal thinking that in the meantime, everything's fine, take off your mask, forget it. It still matters."
President Biden made those comments after announcing the country will have enough vaccines for all adults by the end of May.
But he said it could take until the end of summer to get everyone vaccinated.