WASHINGTON (BLOOMBERG) - US President Donald Trump is no longer considered a coronavirus transmission risk to others and has met the criteria for safe discontinuation of isolation, according to White House physician Sean Conley.

Mr Trump has been fever-free for well over 24 hours and all symptoms have improved, Dr Conley said in a statement published by the White House late on Saturday (Oct 10). He did not say if the president tested negative for the virus.

"The assortment of advanced diagnostic tests obtained reveal there is no longer evidence of actively replicating virus," Dr Conley wrote. "In addition, sequential testing throughout his illness has demonstrated decreasing viral loads."

Dr Conley's update was the first on the president's health since the middle of the week, when he said Mr Trump has been fever-free for more than four days.

The White House has still refused to reveal certain health details about the president and his treatment, including when Mr Trump last tested negative before contracting the coronavirus.

The physician's statement on Saturday said Mr Trump had no fever for more than a day, rather than for the better part of a week, suggesting the president's temperature may have spiked again upon returning to the White House.

Mr Trump gave an 18-minute speech earlier in the day, his first public event since returning from a three-day hospital stint, thanking hundreds of supporters gathered on the South Lawn for their encouragement during his illness.

"I'm feeling great," Mr Trump said from the Blue Room balcony at the White House to invited guests at the campaign-style event. He arrived wearing a mask and removed it before speaking.

Attendees appeared to be mostly masked but were standing close together with no suggestion of social distancing. Hand sanitiser stations and a medical tent were nearby.

The President has announced an aggressive return to the campaign trail following his convalescence, beginning with a rally on Monday night in Orlando. He is expected to visit Pennsylvania on Tuesday and Iowa on Wednesday for additional campaign events.

The President first unveiled his positive test for the coronavirus early on Oct 2, and has credited his recovery to a Regeneron Pharmaceuticals Inc. antibody cocktail he was administered.

The President also received a corticosteroid called dexamethasone as well as Remdesivir, an antiviral manufactured by Gilead Sciences.

Mr Trump also said the United States was "producing powerful therapies and drugs".