Donald Trump falsely claimed he has not changed his tone about the coronavirus outbreak, contending he has always viewed it as "very serious" even after days ago calling the disease "very mild."

"I felt it was a pandemic long before it was declared a pandemic," the president said during a Tuesday White House briefing.

"I have seen that where people actually liked it, but I didn't feel different. ... I've always viewed it as very serious," he claimed after being asked if his tone changed from just a few weeks ago.

But on March 4, he assessed the virus by calling it "very mild." Three days later, he described himself as "not concerned at all."

He also referred to the outbreak as a "hoax" ginned up by Democrats and the news media to take down his presidency. He later contended he was referring to criticism by both that his administration had responded too slowly and inefficiently to the outbreak.

Still, the president's demeanour made a noticeable change on March 9. He had again downplayed the threat to the virus that morning. As he met with GOP campaign donors after a weekend of golfing in Florida, US stock markets tumbled.

The president who boarded Air Force One in Orlando was different than the one who emerged that afternoon from Marine One on the White House's South Lawn. The new Mr Trump has, for the most part, been more stoic and serious -- especially in the White House briefing room -- though he still launches occasional attacks on political foes and critics via his Twitter feed.

Mr Trump appears to be taking the threat more seriously, but he also said he is not close to ordering a national lockdown because some states, like West Virginia, have no or very few confirmed virus cases.

"There are some hotspots that are in trouble, big trouble," he said, like New York and Washington states. "There are areas of the country that don't have problems. They're not going to have problems with hospitals."

But during the Tuesday briefing, he did allow politics to seep in.

When asked to step closer to the podium microphone so television viewers at home could hear his answers, Mr Trump told a Fox News reporter his audience is "very important." Fox viewers make up a large part of Mr Trump's political base -- and he needs them to turn out in big numbers in a handful of swing states if he hopes to win a second term.