To say the president of the United States has never been a fan of the face mask is an understatement – in May he retweeted a Twitter post mocking Democratic presidential challenger Joe Biden for wearing a mask.

But with Covid-19 cases soaring in the US, President Donald Trump has relented – he chose to wear a face mask during a visit to the Walter Reed National Military Medical Center.

Trump was photographed walking with about a dozen officials in the halls of the hospital, wearing a navy-blue mask adorned with a gold presidential seal.

The president was expected to meet combat-wounded service members and their families, as well as health care workers who have been on the front lines of the Covid-19 pandemic.

Trump's remarks were in stark contrast with others he's made on face coverings during the pandemic. Surveys have shown mask wearing has become a topic of partisan debate.

Trump held a rally in June at an indoor arena in Tulsa, Oklahoma, where masks weren't required. An outdoor rally in New Hampshire on Saturday, where mask-wearing was to have been encouraged, was postponed due to a tropical storm in the vicinity.

With poll numbers falling and criticism of his handling of the pandemic rising, Trump appeared to warm to the idea of wearing a mask in recent weeks. He told Fox Business Network on July 1 that "I'm all for masks, I think masks are good" but added that "I don't know if you need mandatory”.