US President-elect Joe Biden has said he will ask Americans to wear masks for his first 100 days in office to curtail the spread of coronavirus.
He told CNN he believed there would be a “significant reduction” in Covid-19 cases if every American wore a face covering.
Mr Biden also said he would order masks to be worn in all government buildings.
The US has recorded 14.1 million cases and 276,000 deaths from Covid-19 – the highest of any country in the world.
Mr Biden is preparing to take office as pharmaceutical giants are poised to ship millions of doses of coronavirus vaccines to the American public.
The UK on Wednesday became the first country in the world to approve the Pfizer vaccine.
In his first joint interview with Vice President-elect Kamala Harris since the election, Mr Biden said: “The first day I’m inaugurated to say I’m going to ask the public for 100 days to mask. Just 100 days to mask, not forever. One hundred days.
“And I think we’ll see a significant reduction if we occur that, if that occurs with vaccinations and masking to drive down the numbers considerably.”
The first 100 days of a new presidency is symbolically important in the US and is seen as a gauge of how a president will get things done.
Constitutional experts say a US president has no legal authority to order Americans to wear masks, but Mr Biden said during the interview he and his Vice-President Kamala Harris would set an example by donning face coverings.