WASHINGTON (NEXSTAR) — The White House COVID-19 response team says the delta variant continues to surge across the country.

During a Thursday briefing, Dr. Anthony Fauci called on Americans to take precautions to stop the virus from mutating.

“The ultimate end game of all this is vaccination,” he said.

He warned that if more Americans don’t get vaccinated, it could mutate into a more dangerous and aggressive strand.

“We have within our power to prevent that,” Fauci said. “You prevent it by not allowing the virus to freely circulate, finding vulnerable targets.”

Already the highly contagious delta variant accounts for 93% of new cases in the U.S.

COVID-19 response coordinator Jeffrey Zients said the message may be sinking in, thanks to added resources and vaccine mandates.

“Over the past 24 hours we’ve recorded 864,000 vaccinations, the highest in a day since July 3,” Zients said.

On Capitol Hill, more and more Republicans are encouraging Americans to get vaccinated to slow the spread of the virus.

But many also argue that mandates from private companies and a mandate for federal workers from the Biden administration go too far.

Sen. Roger Marshall, R-Kan., said the mandates are an “over reaction and unnecessary.”

Marshall, a doctor, says as Americans get more comfortable about the safety of the vaccines, they’ll step up for their shots.

“The good news is the FDA is answering the alarm. We’ve been asking them for several weeks to get the final approval for the vaccines we already have and I think that will kill two birds with one stone,” Marshall said.

The FDA says it hopes to give full approval to the Pfizer vaccine as early as next month.