President Joe Biden called out Republican governors in Texas and Mississippi for what he called "Neanderthal thinking" in deciding to relax their mask mandates and other COVID-19 restrictions.

The governors of both states announced Tuesday they would lift their states' mask mandates and other restrictions on businesses and gatherings aimed at stopping the spread of the virus.

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Biden called it a "big mistake" while speaking in the Oval Office on Wednesday during a meeting with lawmakers, who each wore a mask. He said, "I hope everyone has realized by now, these masks make a difference."

Biden added: "We are on the cusp of being able to fundamentally change the nature of this disease" and said "the last thing we need is Neanderthal thinking that in the meantime, everything's fine, take off your mask, forget it."