"Many people say that it is patriotic to wear a face mask when you can't socially distance. There is nobody more patriotic than me, your favorite President!," Trump tweeted, calling COVID-19 the "Invisible China Virus."
Trump was photographed July 12 touring Walter Reed hospital in Bethesda, Md., while wearing a black mask embroidered with a presidential seal. The photo published Monday was taken during the tour to visit injured service members.
Trump has resisted wearing masks, previously saying he didn't need to because people around him are tested regularly for the coronavirus. On Sunday, during a Fox News interview with host Chris Wallace, Trump said he did not think a national mask mandate was necessary.
But medical advisers from the U.S. Centers for Disease Control and Prevention and U.S. Surgeon General Jerome Adams have advised that wearing a face covering, along with avoiding large gatherings and maintaining social distance, helps slow the spread of the virus.
Trump also faced criticism as Republican governors like Greg Abbott in Texas, Asa Hutchinson in Arkansas and Kay Ivey in Alabama issued statewide mask mandates. First lady Melania Trump and Vice President Mike Pence have been photographed wearing masks.
Walmart is requiring masks inside stores nationwide starting on Monday, and other retailers, including Walgreens, CVS and Lowe's announced that face masks are required to shop in stores nationwide. More than half of U.S. states now have statewide mask requirements.
Trump's action leaves a path for retreat for outliers like Republican Gov. Brian Kemp of Georgia, who on Thursday sued the city of Atlanta for enforcing a mask mandate. Kemp, who has called mask wearing "a good idea," said in June that forcing residents to wear a face covering was "a bridge too far."