President Donald Trump yielded to pressure and wore a face mask in public for the first time on Saturday, as the US posted another daily record for coronavirus cases, while Disney World reopened in a state hit hard by the pandemic.
White House experts leading the fight against the contagion have recommended wearing face coverings in public to prevent transmission of the illness.
But Mr Trump avoided wearing a mask, even after White House staff tested positive for the virus and as more aides began wearing them.
Hours after the World Health Organisation urged countries to step up control measures to rein in the disease, Mr Trump donned a dark mask bearing the presidential seal as he visited wounded veterans at the Walter Reed Military Medical Centre in Bethesda, Maryland.
"I've never been against masks but I do believe they have a time and a place," he told reporters as he left the White House.
In Florida, where nearly one in six of those new infections were recorded, the Walt Disney World theme park partially reopened after four months of shutdown prompted by the virus.
Hundreds of people queued to enter the park in Orlando, some sporting Mickey ears but all wearing face masks, with social distancing and other hygiene precautions also in place.
Mr Trump is trailing Democrat Joe Biden in the polls ahead of a November election, and surveys showed most Americans were unhappy with how he handled the public health crisis.
But the president continued to praise his own response to the pandemic despite a cascade of figures showing the extent of the disease's spread.
The US posted another daily record of confirmed cases on Saturday night, with 66,528 new infections, while the death toll rose by almost 800 to nearly 135,000.
Mr Trump has declined to wear a mask at news conferences, coronavirus task force updates, rallies and other public events. People close to him have said that the president feared a mask would make him look weak and he was concerned that it shifted focus to the public health crisis rather than the economic recovery.
While not wearing one himself, Mr Trump has sent mixed signals about masks, acknowledging that they would be appropriate if worn in an indoor setting where people were close together. But he has accused reporters of wearing them to be politically correct and has retweeted messages making fun of Mr Biden for wearing a mask and implying that Mr Biden looked weak.
Questions remained about whether Mr Trump will wear a mask with any regularity.
The wearing of masks became another political dividing line, with Republicans more resistant to wearing them than Democrats. Few masks were seen at recent Trump campaign events in Tulsa, Oklahoma, Phoenix, Arizona, and Mount Rushmore in South Dakota.
The only time Mr Trump has been known to wear a mask was during a private part of a tour of a Ford car factory in Michigan.
A spokesman for the Biden campaign cast the president's action as too little, too late.
"Donald Trump spent months ignoring the advice of medical experts and politicising wearing a mask, one of the most important things we can do to prevent the spread of the virus," said spokesman Andrew Bates.
"Rather than taking responsibility and leading, he wasted four months that Americans have been making sacrifices by stoking divisions and actively discouraging people from taking a very basic step to protect each other."
