The presumed Democratic presidential candidates called for a federal order for mandatory mask mandate that would apply to all Americans nationwide.
Former Vice President Joe Biden made the demand on Thursday and California Sen. Kamala Harris endorsed the policy.
"Every American should be wearing a mask when they're outside for the next three months at a minimum," Biden told reporters in a media briefing in Wilmington, Delaware.
"Let's institute a mask mandate nationwide starting immediately and we will save lives. The estimates are we will save over 40,000 lives in the next three months if that is done," Biden added.
Harris approved of Biden's statement.
"That's what real leadership looks like," Harris said. "We just witnessed real leadership."
The announcement was made only a day after Harris was announced as Biden's vice presidential pick.
Federal vs. local control
President Donald Trump has resisted calls for a federal mask mandate and has instead left it up to state and local governments to determine their own policies on enforcing social distancing guidelines.
When asked to respond to the suggestion from Biden and Harris, he gave a characteristically dismissive response.
"We do not need to bring the full wait of the government down on law-abiding Americans to accomplish this goal. Americans must have their freedoms, and I trust the American people and their governors very much," President Trump said in his media briefing.
"I trust the American people and the governors want to do the right thing to make the smart decisions and Joe doesn't. Joe doesn't, Joe doesn't, know too much," he continued.
"Unlike the Biden approach, our approach is guided by science," he added. "Sleepy Joe rejects the scientific approach in favor of locking all Americans in their basements for months on end!"
The president went on to accused Biden of wanting to "shut down our economy" and "grind society to a halt" through a federal mandate.
A poll in June found that 76% of Americans thought the lockdown was appropriate or didn't go far enough, while 80% of Americans said that they looked favorably at people who wore masks to stop the spread of the coronavirus.
The U.S. has seen more than 5.2 million confirmed cases of COVID-19 across the country, and the death toll in the U.S. is at more than 166,000 people.
Here's the video of the demand:
BREAKING: Joe Biden, Kamala Harris call for nationwide mask mandate www.youtube.com