US President Donald Trump has made his first public appearance since returning to the White House after COVID, telling his invited supporters the global pandemic was “disappearing”.

Standing alone and not wearing a mask, Mr Trump spoke from the balcony at an event called “a peaceful protest for law and order”, attended by a few hundred people.

His appearance on Saturday is seen as a first step toward resuming full campaigning next week even as his aides remain silent on whether he is still contagious.

The president told the non-mask-wearing crowd who were sent invitations that he was “feeling great”.

Mr Trump also said lockdowns were “unscientific” and a vaccine would be ready “very, very soon”.

Of the coronavirus pandemic he said there were “a lot of flare ups but it’s going to disappear; it’s disappearing”.

LIVE: President @realDonaldTrump delivers remarks at a peaceful protest for law & order https://t.co/BlGvcjjNVX

— The White House 45 Archived (@WhiteHouse45) October 10, 2020

Speaking without hesitation, Mr Trump appeared to be back to his usual rallying form, boasting about his record and hurling unsubstantiated allegations against his opponents as a packed crowd of supporters chanted “we love you”.

“I know you’ve been praying, and I was in that hospital, I was watching down over so many people,” Mr Trump said.

It was the first public event he has held since he was released from hospital on Monday, when some observers watching his return to the White House said he appeared at times to be short of breath.

This time his voice sounded stronger and his complexion was improved but he spoke for only 15 minutes.

Supporters were invited to gather at the South Portico of the White House. Photo: Getty

The White House has not released the results of Mr Trump’s latest COVID-19 test, and has declined to say when he last tested negative.

A White House spokeswoman said on Friday that Trump would be tested for COVID-19 and would not go out in public if it was determined he could still spread the virus.

Mr Trump, who has campaigned on a law-and-order theme during recent months of sometimes violent protests for racial justice, told Saturday’s gathering that the Republican Party had the support of America’s police forces.

“We have law enforcement watching,” he said. “We’re on the side of right.”

National opinion polls show Mr Trump trailing his Democratic challenger Joe Biden by double digits.

But the gap between the two candidates is narrower in the battleground states that may determine who wins the White House.