Dr. Scott Gottlieb, the former commissioner of the Food and Drug Administration, believes the CDC's latest mask guidance will have a "negligible" impact on the new wave of COVID-19 cases, which he continues to think the U.S. will be "through" within the next few weeks. 

Gottlieb reacted on CNBC Wednesday to the Centers for Disease Control and Prevention's announcement that vaccinated people should return to wearing masks indoors in areas with high COVID-19 transmission rates due to the spread of the Delta variant. 

"I think we're further into this Delta wave than we're picking up," Gottlieb said. "I've been saying that for weeks. I think in another two or three weeks, we'll be through this. This new guidance will have a negligible impact on that." 

Gottlieb also told CNBC he doesn't think the U.S. will get "enough bang for our buck by telling vaccinated people they have to wear masks at all times to make it worth our while." The former FDA commissioner previously pointed to the United Kingdom in making his argument that U.S. COVID-19 cases will plateau in the coming weeks, telling CNBC, "If the U.K. is turning the corner, it's a pretty good indication that maybe we're further into this than we think and maybe we're two or three weeks away from starting to see our own plateau here in the United States." 

Meanwhile, CDC Director Rochelle Walensky on Wednesday told CBS This Morning that "if we get people vaccinated" and "if we mask in the interim," the U.S. can "halt" the new wave of cases "in just a matter of a couple of weeks." When asked if the mask guidance could have to get stricter heading into the fall, she said that "I certainly hope we don't have to be in that situation" but that "we will follow the science."